根据短文内容选择正确答案。

Miss Liu: Come on, Children! Let's go to the Water Zoo by school bus.
Children: Great!

(In the Water Zoo)

Miss Liu: Look! This is a bear. What colour is it?

Gao Wei: Wow! It's so big. It's brown. It has small ears.

Li Yan: That's an elephant. It has a short tail (尾巴)and big ears. It's big, too.

Peter: Look at the monkeys! They are in the tree (树). They have long tails.

Gao Wei: And some are eating apples. What lovely monkeys!

Miss Liu: Boys and girls, what's that? It's yellow. It has short legs and a short tail. It can swim.

Can you guess?

Children: Uh…?

Miss Liu: Let's go and find it on the river(河).