-do you clean your room ?-Every day.A. How longB. How oftenC. WhenD. What time

问题补充：

-do you clean your room ?

-Every day.

A. How long

B. How often

C. When

D. What time

答案：

A. How long

(答案→)B. How often

C. When

D. What time

解析：How long多长；How often多久一次；When什么时候；What time 什么时间。根据下文，每天。可知上文问的是，你多久打扫一次房间？故选B。