Read the passage below carefully, and then choose the best answer:
Microwave Magic
The 20th century was a time in which many great inventions were created. Things like the automobile, computers, and the Internet truly changed the way we live forever. Yet, one handy invention that has made eating at home far more convenient is often overlooked. The invention of microwave allowed even the worst cooks in the world to prepare a meal in essentially no time at all. What is really fascinating about microwave ovens is that they were invented by accident. During World War II, British scientists discovered a device called a magnetron that can produce microwaves. They hoped it would help them quickly identify German planes that were intent on bombing their nation. However, it would be an American scientist named Percy Spencer who linked microwaves with cooking food. One day, Spencer brought a candy bar with him to work, and he stored it in his shirt pocket. While walking through a radar set, he noticed that the radar had somehow melted his treat. Afterwards, Spencer and his coworkers started to experiment with heating other things. They tried heating some popcorn kernels and it worked like a charm. Next, they tried to cook an egg with microwaves, but it literally blew up in their face. In 1945, the company that Spencer worked for, Raytheon, filed a patent for the technology and started working on ways to make microwave ovens more efficient. The first commercial microwave ovens hit the market, and an industry was born. In the first few years, things didn’t appear too promising. Early microwaves were quite expensive and they were big and chunky, so it was difficult to fit them in most kitchens. Yet, people did see the benefit an ease of being able to cook foods so quickly. Therefore, once manufacturers were able to shrink the device and bring down the price a bit, sales started to skyrocket. By 1986, approximately 25 percent of Americans had a microwave oven in their kitchen. Through the years, many people have questioned the safety and potential negative health effects of microwaves, fearing that the technology was a little too good to be true. Yet, some studies have shown that microwaving food actually helps it to retain more nutrients because of the short cooking times and minimal water required. However, it is essential to use microwave containers to avoid harmful chemicals from possibly leaking into your food. Microwave dishes may never be seen as gourmet cooking, but when you are in a hurry, nothing beats this method of cooking.
7. What does the author suggest about the safety of microwaves?
