单项选择题

The experiment with the dove indicated that ______.

A．birds have to be taught to navigate
B．a bird that has been caged will not fly long distances
C．some birds cannot fly at night
D．some birds seem to follow the stars when they fly at night

<上一题目录下一题>

热门试题

单项选择题

By his outdoor cousins the author means ______.

A．other experimenters
B．the other doves of the same brood
C．doves under the natural sky
D．other birds in general

单项选择题

During daylight hours, birds ______.

A．fly aimlessly
B．rely on landmarks
C．use sun for guidance
D．are more likely to get lost