--- does she chat with friends on the Internet?
--- Once a week.
A. How long
B. How often
C. How many times
D. How much
网友回答
A. How long
(答案→)B. How often
C. How many times
D. How much
解析：How long多长；How often多久一次；How many times多少次；How much多少钱。根据下文，每周一次。可知上文提问的是频率，故选B。