does your cousin go to the gym? -- Twice a week.A. How long B. How often C. How soon

问题补充：

-- does your cousin go to the gym?

-- Twice a week.

A. How long B. How often C. How soon

答案：

解析：根据回答一周两次，故上句应该提问频度，A. How long多长用for +一段时间 B. How often 提问频度C. How soon多久用in + 一段时间回答,故选B。