单项选择题

Questions 14 to 17 are based on the following passage. At the end of the passage, you will be given 20 seconds to answer the questions. Now, listen to the passage.
How did people predict the weather in the past

A.By watching the stars at night.
B.By studying the weather map.
C.By examining pictures drawn by scientists.
D.By observing the weather with their eyes.