Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions:

Around 150 B.C. the Greek astronomer Hipparchus developed a system to classify stars according to brightness.

Suy nghĩ và trả lời câu hỏi trước khi xem đáp án

ATNETWORK
ADMICRO
YOMEDIA
ZUNIA9