－ do you go to Old People’s Home?
－Twice a month.
A. How long
B. How soon
C. How often
D. How many times
网友回答
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，一个月两次。可知上文提问频率，故选Ｃ。