—I always lose ________ when studying.

—Maybe you should quit staring at all the cute boys.

A. concentration　　　　　　　　　　　　 B. construction

C. conversation　　　　　　　　　　　　　 D. communication

- I always lose ________ when studying.

- Maybe you should quit staring at all the cute boys.

A．concentration          B．construction          C．conversation         D．communication