do you play football?　- Once a week.A. How much B. How long C. How often D. How fa

问题补充：

--- do you play football?

--- Once a week.

A. How much

B. How long

C. How often

D. How far

答案：

A. How much

B. How long

(答案→)C. How often

D. How far

解析：本题是对疑问副词词组的考察，通过答句可以判断出是询问动作发生的频率，所以选择C选项的how often。