题目内容：

Frogs are animals that can live both in water and on land. There are more than 5,000 kinds of frogs on the earth. The earliest known frogs lived about 190 million years ago and the frogs today still look the same. Here are some fun things that you might not know about frogs. Enjoy!

The Biggest and the Smallest Frogs

Some frogs can be very big. The biggest kind of frog is the Goliath Frog in West Africa. Its body can be nearly 30cm long, about the size of a large cat. The Gold Frog and the Poison Frog are the smallest frogs in the world. They are less than 1cm long. Though the Poison Frog is very small, it is not weak at all. It is dangerous. Any animal that eats it will die very soon.

The Best Jumpers

Frogs are very good at jumping. They developed jumping legs so that they would not be eaten by other large animals. Using their big strong legs, more frogs can jump over 20 times their own length. The Australian Rocket Frog can even jump over 2m, which is 50 times its body length (5.5 cm). That might be the reason why frogs are called the best jumpers on the earth.

The Cryogenic Animal

Some frogs like the Common Wood Frog have a special ability to live in very cold places. When the temperature goes down, they become ice frogs. 2/3of their body water freezes. Their hearts stop, and their breathing stops too. You may think they are dead, but in fact they are not. Maybe we humans can learn the way that the frogs do for medical purpose.

1.The earliest frogs lived about          million years ago.

A．20

B．30

C．50

D．190

2.      can jump over 2m.

A．The Goliath Frog

B．The Common Wood Frog

C．The Poison Frog

D．The Australian Rocket Frog

3.What will happen to a Common Wood Frog at very low temperature?

A．It will die very soon.

B．It will be an ice frog.

C．It will become dangerous.

D．It will become very small.