当前位置:在线题库搜索>[单选题]The trainer usually gives the animal a piece of candy or fruit _______.( )的答案是什么?

问题:

[单选题]The trainer usually gives the animal a piece of candy or fruit _______.( )

A、before it plays a trick
B、when it is hungry
C、after it has done the trick
D、when it starts to play a trick

参考答案: D