— do you go to the library?— Every week.A. How longB. How soonC. How oftenD. How many tim

问题补充：

— do you go to the library?

— Every week.

A. How long

B. How soon

C. How often

D. How many times

答案：

A. How long

B. How soon

(答案→)C. How often

D. How many times

解析：How long多长；How soon多久；How often多久一次；How many times多少次。根据下文，每星期。可知上文提问频度，故选C。