
提问人:网友13***556
发布时间:2022年4月6日 06:40
[单项选择题]
Passage One Although no one is certain why migration occurs, there are several theories....Why did one scientist expose birds to artificial daylight
A.To test the relationship between daylight and a disease of the glands common to birds.
B.To test the relationship between daylight and migration.
C.To test the relationship between migration and temperature.
D.To test the relationship between daylight and changes in the season.

