24（）

单项选择题The main idea of the whole story is that （）.

A．there is more food and water in space than on earth
B．eating and drinking in space is a special problem
C．astronauts can never eat or drink in a spaceship
D．there is no food or water in a spaceship

单项选择题Why can’t astronauts drink water from cups（）

A．The water would come from the open cups.
B．The water would spill all over their food.
C．Crumbs would float in the cups.
D．The cups would float in the air.