香港和澳门都发达的经济部门是（　　）

阅读短文，选出合适的一项。

A: picture

A: Look! I have a picture. What can you see on the wall, Tim?

B: I can see a map of China.

A: Where is Wuhan? Do you know?

B: Sorry, I can't find it.

A: Where's Beijing?

B: It's here.

A: Can you see the children?

B: Yes, I can. Who are they?

A: Look, the two American girls are Lucy and Lily. The flowers are in Lucy's hands, Lily is behind the desk. The girl in red is Han Mei. The boy is Wang Ming. His kite is on the wall. That's Jim. His football is under the desk.

一般地，形如____的函数是二次函数．