Choose the best answer:
I think the light bulb the most important ____________.

Choose the item (A, B, C or D) that best completes each of the following sentences. 
In 1988, for the first time in British history, a National Curriculum was introduced. The National Curriculum tells pupils which subjects they have to study, what they must learn and when they have to take assessment tests. [assessment: đánh giá] 
Between the ages of 14 and 16, pupils study for their GCSE (General Certificate of Secondary Education) exams. Pupils must take English Language, Maths and Science for GCSE, as well as a half GCSE in a foreign language and Technology. addition, they must also be taught Physical Education, Religious Education and Sex Education, although they do not take exams in these subjects. 
At the age of 16, pupils can leave school. If pupils stay on, they usually take A (Advanced) levels, AS (Advanced Supplementary) level or GNVQs (Greater National Vocational Qualifications). It is quite common to combine, for example, two A levels with one AS level, or one A level with one GNVQ. 
Pupils taking A levels study traditional subjects, such as French, Physics or History. To go to university, pupils usually need two or three A levels. 
AS levels are the same standard as A levels, but only half of the content: AS level German. Pupils take the A-level German language exam, but do not take the A-level German Literature exam. 
GNVQs are vocational qualifications. Pupils usually take on GNVQ in subjects such as Business, Leisure and Tourism, Manufacturing, and Art and Design. One GVNQ (at advanced level) is equal to two A levels.

Which of the following subjects do British students NOT take exams in? 

Read the following passage and choose the best answer for each blank.

The General Certificate of Secondary Education or the GCSE examinations for (26) _____ are the standard school-leaver qualifications taken by (27) _____ all UK students in the May and June following their 16th birthday. If you come to a UK (28) _____ school before you (29) _____ the age of 16, you will study towards GCSE examinations in up to 12 subjects. Some subjects are compulsory, including English arid mathematics, and you can select (30) _____, such as music, drama, geography and history from a series of options. GCSEs provide a good all-round education (31) _____ you can build on at college and eventually at university. AS- and A-levels are taken after GCSEs. They are the UK qualifications most (32) _____ accepted for entry to university and are available in subjects from the humanities, arts, sciences and social sciences as well as in (33) _____ subjects such as engineering, and leisure and tourism. You can study up to four subjects at (34) _____ same time for two years, (35) _____ AS-level examinations at the end of your first year (called the lower-sixth) and A-level qualifications at the end of your second year (called the upper-sixth).

(31) _____

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
There is a common expression in the English language referring to a blue moon. When people say that something happens “only once in a blue moon,” they mean that it happens only very rarely, once in a great while. This expression has been around for at least a century and a half; there are references to this expression that date from the second half of the nineteenth century. (5) The expression “a blue moon” has come to refer to the second full moon occurring in any given calendar month. A second full moon is not called a blue moon because it is particularly blue or is any different in hue from the first full moon of the month. Instead, it is called a blue moon because it is so rare. The moon needs a little more than 29 days to complete the cycle from full moon to full moon. Because every month except February has more than 29 days, every month will have at least one full moon (except February, which will have a full moon unless there is a full moon at the very end of January and another full moon at the very beginning of March). It is on the occasion when a given calendar month has a second full moon that a blue moon occurs. This does not happen very often, only three or four times in a decade. The blue moons of today are called blue moons because of their rarity and not because of their color; however, the expression “blue moon” may have come into existence in reference to unusual circumstances in which the moon actually appeared blue. Certain natural phenomena of gigantic proportions can actually change the appearance of the moon from Earth. The eruption of the Krakatao volcano in 1883 left dust particles in the atmosphere, which clouded the sun and gave the moon a bluish tint. This particular occurrence of the blue moon may have given rise to the expression that we use today. Another example occurred more than a century later. When Mount Pinatubo erupted in the Philippines in 1991, the moon again took on a blue tint.

How many blue moons would there most likely be in a century?

Read and choose best answers the question about the passage:

"Education is not an end, but a means to an end. In other words, we do not educate children only for the purpose of educating them. Our purpose is to fit them for life.
 
In some modem countries it has, for some time, been fashionable to think that by free education for all - whether rich or poor, clever or stupid - one can solve all the problems of society and build a perfect nation. But we can already see that free education for all is not enough; we find in such countries a larger number of people with university degree; they refuse to do what they think “low” work; and, in fact, work with hands is thought to be dirty and shameful in such countries. But we have only to think a moment to understand that the work of a completely uneducated farmer is far more important than that of a professor; we can live without education, but we die if we have no food. If no one cleaned our streets and took the rubbish away from our house, we should get terrible diseases in your towns.
 
In fact, when we say that all of us must be educated to fit us for life, it means that we must be educated in such a way that, firstly, each of us can do whatever work suited to our brains and ability and, secondly, that we can realize that all jobs are necessary to society, and that is very bad to be ashamed of one’s work. Only such a type of education can be considered valuable to society."

2. The writer wants to prove that ……..

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions.
When John Mills was going to fly in an airplane for the first time, he was frightened. He did not like the idea of being thousands of feet up in the air. "I also didn't like the fact that I wouldn't  be in control," says John.
"I'm a terrible passenger in the car. When somebody else is driving, I tell them what to so. It drives everybody crazy."
However John couldn't avoid flying any longer. It was the only way he could visit his grandchildren in Canada.
"I had made up my mind that I was going to do it, I couldn't let my son, his wife and their three children travel all the way here to visit me. It would be so expensive for them and I know Tom's business isn't doing so well at the moment - it would also be tiring for the children - it's a nine-hour flight!" he says.
To get ready for the flight John did lots of reading about airplanes. When he booked his seat, he was told that he would be flying on a Boeing 747, which is better known as a jumbo jet. "I  needed to know as much as possible before getting in that plane. I suppose it was a way of making myself feel better. The Boeing 747 is the largest passenger aircraft in the world at the moment.
The first one flew on February 9th 1969 in the USA. It can carry up to 524 passengers and 3.400 pieces of luggage. The fuel for airplanes is kept in the wings and the 747's wings are so big that they can carry enough fuel for an average car to be able to travel 16,000 kilometers a year for 70 years. Isn't that unbelievable? Even though I had discovered all this very interesting information about the jumbo, when I saw it for the first time, just before I was going to travel to Canada, I still couldn't believe that something so enormous was going to get up in the air and fly. I was even more impressed when I saw how big it was inside with hundreds of people!"
The biggest surprise of all for John was the flight itself. "The take-off itself was much smoother than I expected although I was still quite scared until we were in the air. In the end, I managed to relax, enjoy the food and watch one of the movies and the view from the window was spectacular. I even managed to sleep for a while!
"Of course," continues John, "the best reward of all was when I arrived in Canada and saw my son and his family, particularly my beautiful grandchildren. Suddenly, I felt so silly about all the years when I couldn't even think of getting on a plane. I had let my fear of living stop me from seeing the people I love most in the world. I can visit my son and family as often as I like now!" Question 24: Why did John Mills fly in an airplane?

How did John feel when the airplane was taking off?

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions:
On March 15, Dunes View Middle School held a contest for school bands. Student bands tried  out for the opportunity to perform at the school picnic, which will be held at the end of June. The winner of the contest was the band called Four Square. "We're very proud that we won the contest  and are excited to perform at the picnic," says Peter Zandt, who plays the guitar in the band. "And     since we hope to perform someday at other local places, like restaurants and parks, this will be  a  great first step."
The contest was the creation of music teacher Mr. Lopez and drama teacher Ms. Cho. The two thought of the idea while discussing recent years' school picnics. "The picnic is one of the biggest events of the year, but it has become a bit formulaic ," said Ms. Cho. "The activities are the same every year. We thought that a performance by a student band would make the school picnic more interesting and fun." Mr. Lopez, Ms. Cho, and three other teachers judged the contest, which took place  in the gym. Eight student bands signed up to audition. The bands varied in their musical forms: there  were several rock bands, a folk band, and even a jazz band. "I'm disappointed that my band didn't win,  but I think the judges made the right choice," says student Marisol Varga, a member of the folk trio called The Bell Girls. "Four Square is really excellent."
To see if the bands could present a wide range of musical skills, the teachers asked them  each to prepare two songs: one song with original words, and another in which students played instrumental music only. The judges finally chose the band Four Square as the winner of the contest. Four Square is a rock band with an unusual twist: it includes a violin player! The members of Four Square write their own songs and practice three times a week after school. Students and teachers agreed that the band competition was a big success. All are  looking forward  to the school picnic in June.

According to the article, what does the band Four Square hope to do in the future?

On Friday, April 14, the city hall’s electricity is scheduled to be shut down at 7 A.M. and restored at 6 P.M. The building ---131--- for the day. During the power outage, the emergency lighting system will be upgraded. ---132---, all circuit panels will be replaced to bring them into compliance with current safety codes.---133--- exiting city hall offices on Thursday, please disconnect all desktop computers, wireless servers, and other computer-related equipment. Furthermore, employees are asked to remove any personal contents from the kitchenette.---134---.Please direct questions or concerns to the director of building maintenance.

132........................

Choose the letter A, B, C or D to complete the passage below.

"The Internet was born (1) _________scientists attempted to connect the American Defence Network to other satellite networks in (2) _________to exchange information. Soon, scientific and educational institutions as well as research departments became interested (3) _________ linking up, and, before long, the Internet had expanded into an international information and communication network.

The Internet now (4) _________ all the countries in the world. You can be connected to the Internet directly through your own computer or you can hook up to (5) _________ access system which allows you to use some of the Internet’s services."

5. You can be connected to the Internet directly through your own computer or you can hook up to (5) _________ access system which allows you to use some of the Internet’s services.

The Midwest Artisanal Cheese Guild (MACG) organizes trade shows and conducts educational seminars ---135--- the cheese-crafting trade within the Midwestern United States. Cheeses from this region are recognized internationally. Many of---136--- cheeses are used by chefs at restaurants around the world.
The MACG puts on the region’s largest cheese-maker exposition, held each year in April. The prestigious Wizard of Cheese contest is held at this event. ---137---. Dan Travella was last year’s---138---. His aged cheddar cheese received a winning score of 98.7 out of 100.

135..................

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
As the twentieth century began, the importance of formal education in the United States increased. The frontier had mostly disappeared and by 1910 most Americans lived in towns and cities. Industrialization and the bureaucratization of economic life combined with a new emphasis upon credentials and expertise to make schooling increasingly important for economic and social mobility. Increasingly, too, schools were viewed as the most important means of integrating immigrants into American society.
The arrival of a great wave of southern and eastern European immigrants at the turn of the century coincided with and contributed to an enormous expansion of formal schooling. By 1920 schooling to age fourteen or beyond was compulsory in most states, and the school year was greatly lengthened. Kindergartens, vacation schools, extracurricular activities, and vocational education and counseling extended the influence of public schools over the lives of students, many of whom in the larger industrial cities were the children of immigrants. Classes for adult immigrants were sponsored by public schools, corporations, unions, churches, settlement houses, and other agencies.
Reformers early in the twentieth century suggested that education programs should suit the needs of specific populations. Immigrant women were once such population. Schools tried to educate young women so they could occupy productive places in the urban industrial economy, and one place many educators considered appropriate for women was the home.
Although looking after the house and family was familiar to immigrant women, American education gave homemaking a new definition. In preindustrial economies, homemaking had meant the production as well as the consumption of goods, and it commonly included income-producing activities both inside and outside the home, in the highly industrialized early-twentieth-century United States, however, overproduction rather than scarcity was becoming a problem. Thus, the ideal American homemaker was viewed as a consumer rather than a producer. Schools trained women to be consumer homemakers cooking, shopping, decorating, and caring for children "efficiently" in their own homes, or if economic necessity demanded, as employees in the homes of others. Subsequent reforms have made these notions seem quite out-of-date

It can be inferred from paragraph 1 that one important factor in the increasing importance of education in the United States was     .

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
Less than a year ago marketing director, David Smith, 33 was behaving like a secet agent. He used to secretly taped all his conversations, he refused to sign his name and he would ask his secretary to check all his emails. Anything he wrote was photocopied and kept as “evidence”. But David isn’t mad, or even mildly eccertric. He suffers from ‘resposibility OCD’, one of more common form of obsessive compulsive disorder, or OCD, as it is usually known.
OCD is now recognized as the second most prevalent mental-health problem, after depression – and the number of reported cases is soaring. Experts estimate that 2% - 3% of the population suffer from the full-blown syndrome, with as many as one in five suffering from a milder form.
OCD sufferers are tortured by obsessional thoughts, such as worrying that their hands are contaminated by germs. The terrible anxiety is only relieved by performing a particular set of behaviours. Unfortunately, any sense of relief is short-lived, which is why the behaviour must be repeated again and again. OCD sufferers know their behavior is irrational, yet feel powerless to stop.
Common treatments are either antidepressants or behavioral therapy with a psychologist, but only 60% of patients show some improvement. However, a new treatment from America is bringing fresh hope to sufferers.
One of the OCD gurus and neuropsychiatrists, Jeffrey Schwartz, has designed the Four Steps program which employs meditation teachniques with the aim of teaching sufferers to manage their symptoms by themselves. “The goal is to learn to override false brain messages”, explains Schwartz.
There are different theories about what causes the disorder. Most experts recognize a genetic element that can be triggered by a stressful event. Schwartz believes that the OCD ‘worry circuit’ is a
direct result of faulty brain chemistry. ‘When someone experiences an OCD thought, one part of the brain knows quite clearly that the hand are not dirty’, explains Schwartz ‘Some part of the brain is standing apart from the symptoms, reflecting on the sheer bizarreness of it all. The objective is to harness this impartial spectator so that patients can use this healthy part of their brain to resist the compulsions.’
David Smith is delighted with the results of Schwartz’s treatment. ‘Now I can sign cheques without a problem’, he says brightly. ‘And I don’t photocopy them either. OCD used to feel like a huge stigma, but I don’t feel handicapped by it any more. You just deal with it.’

What does the word ‘their’ in paragraph 5 refers?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
One of the most important battles of the American Civil War occurred around the small town of Gettysburg, Pennsylvania, from July 1 to July 3, 1863. What began as a search for shoes by the Confederate Army quickly escalated into a major battle. As the Confederate soldiers sought new shoes, they unexpectedly encountered Union cavalry stationed west of the town at Willoughby Run, and the battle began. After much fighting and heavy casualties on both sides, the Confederates pushed the Union forces back through the town of Gettysburg, where they regrouped south of the town along the high ground near a cemetery.
Confederate General Robert E. Lee ordered General R.S. Ewell to seize the high ground from the battle - weary Union soldiers "if practical." Ewell hesitated in the attack, giving the Union troops a chance to establish a stronghold along Cemetery Ridge and then bring in reinforcements with artillery. By the time Lee realized Ewell had not attacked, the opportunity had vanished. Other failures by the Confederates included the generals' opposition to the attack plans and a lack of information about Union defense. This combination of errors allowed the Union forces to win a critical victory in the Civil War. By the end, a total of 160,000 men were involved in this fierce and bloody battle.

The word “escalated” in paragraph 1 could best be replaced by     .

Klok Financial has recently updated its employee handbook. ---143--Although the information concerning benefits and terms of employment remains the same, other important modifications have been made. This version of the handbook includes new policies concerning e-mail privacy, Internet use, and the use of mobile devices. Our travel guidelines have also been 144---. The process for
reimbursement after a trip is now much more efficient.

All employees must attend an informational session about the policies. One-hour sessions will be held at 10 A.M. on 9 July and 16 July. ---145, employees will be required to sign a form acknowledging that they have received, read, and understood the information contained in the handbook and that they accept the terms. Please arrange with your manager ---146--- one of these sessions.

144................

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

Researchers in the field of psychology have found that one of the best way to make an important decision, such as choosing a university to attend or business to invest in, involves the utilization of a decision worksheet. Psychologists who study optimization compare the actual decisions made by people to theretical ideal decisions to see how similar they are. Proponents of the worksheet procedure believe that it will yield optimal, that is, the best decisions. Although there are several variations on the exact format that worksheets cam take, they are all similar in their essential aspects.

Worksheets require defining the problem in a clear and concise way and then listing all possible solutions to the problem. Next, the pertinent considerations that all possible solutions to the problem. Next, the pertinent considerations that will be affected by each decision are listed, and the relative importance of each consideration or consequence is determined. Each consideration is assigned a numerical value to reflect its relative importance. A decision is mathematically calculated by adding these values together. The alternative with the highest number of points emerges as the best decision.

Since most important problems are multifaceted, there are several alternatives to choose from, each with unique advantages and disadvantages. One of the benefits of a pencil and paper decision-making procedure is that it permits people to deal with more variables than their minds can generally comprehend and remember. On the average, people can keep about seven ideas in their minds at once. A worksheet can be especially useful when the decision involves a large number of variables with complex relationships. A realistic example for many college students is the question "What will I do after graduation?" A graduate might seek a position that offers specialized training, pursue an advanced degree, or travel abroad for a year.

A decision-making worksheet begins with a succinct statement of the problem that will also help to narrow it. It is important to be clear about the distinction between long-range and immediate goals because long-range goals often involve a different decision than short-range ones. Focusing on long-range goals, a graduating student might revise the question above to "What will I do after graduation that will lead to a successful career?"

What does the passage mainly discuss?

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions:
Environmental pollution is one of the impacts of human activities on the Earth. Pollution occurs when pollutants contaminate the natural surroundings; which brings about changes that affect our normal lifestyles adversely. Pollution disturbs our ecosystem and the balance in the environment. Pollution occurs in different forms; air, water, soil, radioactive, noise, heat/ thermal and light Let us discuss the causes and effects of air pollution on mankind and the environment as a whole.
Air pollution is the most prominent and dangerous form of pollution. It occurs due to many reasons. Excessive burning of fuel which is a necessity of our daily lives for cooking, driving and other industrial activities; releases a huge amount of chemical substances in the air every day; these pollute the air. Smoke from chimneys, factories, vehicles or burning of wood basically occurs due to coal burning; this releases sulphur dioxide into the air making it toxic.
The effects of air pollution are evident too. The increase in the amount of CO2 in the atmosphere leads to smog which can restrict sunlight from reaching the earth. Thus, preventing plants in the process of photosynthesis. Gases like sulfur dioxide (SO2) and nitrogen oxide (NO) can cause acid rain.
The decrease in quality of air leads to several respiratory problems including asthma or lung cancer. Chest pain, congestion, throat inflammation, cardiovascular disease, respiratory disease are some of diseases that can be caused by air pollution.
The emission of greenhouse gases particularly CO2 is leading to global warming. Every other day new industries are being set up, new vehicles come on roads and trees are cut to make way for new homes. All of them, in direct or indirect way lead to increase in CO2 in the environment. The increase in CO2 leads to melting of polar ice caps which increases the sea level and pose danger for the people living near coastal areas.
Ozone layer is the thin shield high up in the sky that stops ultra violet rays from reaching the  earth. As a result of human activities, chemicals, such as chlorofluorocarbons (CFCs), were released into the atmosphere which contributed to the depletion of ozone layer.

According to the passage, which of the following sentences is NOT true?

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks
 Few people now realize the reality of global warming and its effects on the world’s climate. Many scientists (26)...... the blame for recent natural disasters on the increase in the world’s temperatures and are convinced that, more than ever before, the Earth is  at (27)........ from the forces of the wind, rain and sun. According to them, global warming is making extreme weather events, such as hurricanes and droughts, even more severe and causing sea levels all around the world to rise.
Environmental groups are putting pressure on governments to take action to reduce the amount of carbon dioxide which is given (28)....... by factories and power plants, thus attacking the problems at its source. They are in  (29)........... of more money being spent on research into solar, wind and wave energy devices, which could then replace existing power (30)......... . Some scientists, however, believe that even if we stopped releasing carbon dioxide and other gases into the atmosphere tomorrow, we would have to wait several hundred years to notice the results. Global warming, it seems, is to stay.

(26)............................

Choose the item (A, B, C or D) that best completes each of the following sentences. 
In 1988, for the first time in British history, a National Curriculum was introduced. The National Curriculum tells pupils which subjects they have to study, what they must learn and when they have to take assessment tests. [assessment: đánh giá] 
Between the ages of 14 and 16, pupils study for their GCSE (General Certificate of Secondary Education) exams. Pupils must take English Language, Maths and Science for GCSE, as well as a half GCSE in a foreign language and Technology. addition, they must also be taught Physical Education, Religious Education and Sex Education, although they do not take exams in these subjects. 
At the age of 16, pupils can leave school. If pupils stay on, they usually take A (Advanced) levels, AS (Advanced Supplementary) level or GNVQs (Greater National Vocational Qualifications). It is quite common to combine, for example, two A levels with one AS level, or one A level with one GNVQ. 
Pupils taking A levels study traditional subjects, such as French, Physics or History. To go to university, pupils usually need two or three A levels. 
AS levels are the same standard as A levels, but only half of the content: AS level German. Pupils take the A-level German language exam, but do not take the A-level German Literature exam. 
GNVQs are vocational qualifications. Pupils usually take on GNVQ in subjects such as Business, Leisure and Tourism, Manufacturing, and Art and Design. One GVNQ (at advanced level) is equal to two A levels.

Which of the following subjects do pupils NOT take on GNVQ in? 

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions.
When John Mills was going to fly in an airplane for the first time, he was frightened. He did not like the idea of being thousands of feet up in the air. "I also didn't like the fact that I wouldn't  be in control," says John.
"I'm a terrible passenger in the car. When somebody else is driving, I tell them what to so. It drives everybody crazy."
However John couldn't avoid flying any longer. It was the only way he could visit his grandchildren in Canada.
"I had made up my mind that I was going to do it, I couldn't let my son, his wife and their three children travel all the way here to visit me. It would be so expensive for them and I know Tom's business isn't doing so well at the moment - it would also be tiring for the children - it's a nine-hour flight!" he says.
To get ready for the flight John did lots of reading about airplanes. When he booked his seat, he was told that he would be flying on a Boeing 747, which is better known as a jumbo jet. "I  needed to know as much as possible before getting in that plane. I suppose it was a way of making myself feel better. The Boeing 747 is the largest passenger aircraft in the world at the moment.
The first one flew on February 9th 1969 in the USA. It can carry up to 524 passengers and 3.400 pieces of luggage. The fuel for airplanes is kept in the wings and the 747's wings are so big that they can carry enough fuel for an average car to be able to travel 16,000 kilometers a year for 70 years. Isn't that unbelievable? Even though I had discovered all this very interesting information about the jumbo, when I saw it for the first time, just before I was going to travel to Canada, I still couldn't believe that something so enormous was going to get up in the air and fly. I was even more impressed when I saw how big it was inside with hundreds of people!"
The biggest surprise of all for John was the flight itself. "The take-off itself was much smoother than I expected although I was still quite scared until we were in the air. In the end, I managed to relax, enjoy the food and watch one of the movies and the view from the window was spectacular. I even managed to sleep for a while!
"Of course," continues John, "the best reward of all was when I arrived in Canada and saw my son and his family, particularly my beautiful grandchildren. Suddenly, I felt so silly about all the years when I couldn't even think of getting on a plane. I had let my fear of living stop me from seeing the people I love most in the world. I can visit my son and family as often as I like now!" Question 24: Why did John Mills fly in an airplane?

What does the word "which" in the paragraph refer to?

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questions.
                      My first home
When my parents married, they rented a small house and they didn’t have a lot of money for furniture. The kitchen had a sink for washing up and a cooker, but that was all. They (6)............. a old table and a chair from the market. They borrowed a sofa (7)....... _was also old but they covered it with modern materials so it was bright and cheerful.
Outside, there was a small garden behind the house, but in front of it there was only the road. (8).........., the road wasn’t busy, so I could cross it to reach the park on the opposite side. We   lived there (9)..........I was ten and we were very happy. We had to move house because it was too small when my twin sisters were born. We all (10).......... sad when we left.

(8)..........................

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
A team of Russian scientists has challenged the theory that the woolly mammoths became extinct 10,000 years ago at the end of the Ice Age. The scientists have reported that the beasts may have survived until 2000 B.C. on an island off the coast of Siberia, where researchers uncovered 29 fossilized woolly mammoth teeth ranging in age from 4,000 to 7,000 years. The question to be asked now is, how did these prehistoric pachyderms survive in their island environment? One possibility is that they adapted to their confined surroundings by decreasing their bulk. This theory is based on their smaller tooth size, which  has led scientists to believe that they were only 6 feet tall at the shoulder compared with 10 feet of their full-sized counterpart. But would this be enough to enable them to survive thousands of years beyond that of other mammoths? Researchers are still working to uncover the reasons for this isolated group's belated disappearance.

According to the passage, some researchers suggest that mammoths became extinct