—do you go to the gym?—Twice a month.A. How manyB. How muchC. How oftenD. How far

问题补充：

—do you go to the gym?

—Twice a month.

A. How many

B. How much

C. How often

D. How far

答案：

A. How many

B. How much

(答案→)C. How often

D. How far

解析：Howfar多远；How many多少，修饰可数名词复数；How often多久一次；How much多少钱。根据回答，一个月两次，故选C。