阅读理解(Reading comprehension)：

　　Scientists can tell just how hot the surface of the moon get when it faces the sun, and how cold it becomes it turns away. The side of the moon toward the sun gets two degrees hotter than boiling water, while the night side reaches 243 degree below zero.

　　In an eclipse(月蚀), the earth's shadow falls on the moon. Then the moon's temperature may drop 300 degrees in a very short time.

　　A temperature change like this cannot happen on the earth, but why does it happen on the moon? Scientists think that the surface of the moon is dust. On the earth, rocks store heat from the sun. When the sun goes down, the rocks stay warm. But the dust of the moon cannot do this. So when the moon becomes dark, the heat goes away quickly, and it gets very cold.

1．Scientists have found that the moon's surface is ________.

[　　]

A．always hotter than 100 degrees

B．either very hot or very cold compared with the temperature on the earth

C．usually many degrees below zero

D．about the same as that of the earth

2．Temperatures on the moon change ________.

[　　]

A．very rapidly

B．by only a few degrees

C．very slowly

D．only when there is an eclipse

3．The surface of the moon is probably ________.

[　　]

A．rock that stores heat

B．dust that cannot store heat

C．dust that stores heat

D．rock that does not store heat