题目内容：

Birds live in trees. But do you know that some frogs live in trees, too?

Yesterday my cousin told me something about tree frogs.

Tree frogs are not easy to find. They can change their colours. On green leaves, they stay green. On a brown tree, they turn brown. Some tree frogs can change from green to gold or blue.

Tree frogs have legs and big feet. They have sticky(黏的) pads on the end of their toes. These toe pads keep them from falling from the trees.

Tree frogs can be all different colours. Their eyes are of different colours, too. Some have green eyes, and some have grey eyes. Some frogs’ eyes are gold, and some are bright red. The sounds they make are different, too. One frog makes a sound like dog barking（狗叫）. Another frog makes a loud noise like a snore（打呼噜）. There is even a frog that whistles(口哨)!

1.Why are tree frogs difficult to find?

A. Because they have sticky pads.

B. Because they can change colours.

C. Because they can stand on their toes.

D. Because they can make dog barking sounds.

2.In summer, what colour may a tree frog be when it’s in green leaves?

A. Green. B. Yellow. C. Blue. D. Brown.

3.The sticky pads ______.

A. can change frogs’ sounds

B. can change frogs’ colours

C. can help tree frogs jump faster

D. can stop frogs from falling from the trees

4.The last paragraph tells us that ______.

A. tree frogs make barking sound in spring

B. tree frogs make noisy sounds in summer

C. tree frogs can make whistling sounds

D. tree frogs are different in eye colours and sounds

5.From the passage we know that ______.

A. frogs all look the same

B. tree frogs live under trees

C. there are many different kinds of frogs

D. all frogs have red eyes and make the same sounds