— do you go to Dalian on business?—Never.A. How long B. How often C What time D. When

问题补充：

— do you go to Dalian on business?

—Never.

A. How long B. How often C What time D. When

答案：

解析：How long多长；How often多久一次；What time什么时间；When什么时候。根据下文，从来没有，可知上文提问频率，故选B。