─did they go to work last week ?─Once .A. How many timesB. How oftenC. How soonD. How long

问题补充：

─did they go to work last week ?─Once .

A. How many times

B. How often

C. How soon

D. How long

答案：

(答案→)A. How many times

B. How often

C. How soon

D. How long

解析：从答语一次来看，前面问的应该是多少次，所以选A多少次。