-- Would you please your radio a little? I can hardly go to sleep.-- Oh sorry.A. turn off

问题补充：

-- Would you please your radio a little? I can hardly go to sleep.

-- Oh, sorry.

A. turn off

B. turn on

C. turn down

D. turn up

答案：

A. turn off

B. turn on

(答案→)C. turn down

D. turn up

解析：根据后文内容I can hardly go to sleep.和radio后接a little，可知答案为C，意思是将收音机音量调小点。