— How much is it if you ______ 5 ______ 20?

— The answer is 100. [ ]

A. add, and

B. subtract, from

C. multiply, by

D. divide, by

办税服务厅实行领导值班制，值班领导由县税务局局领导和相关科（室）负责人轮流担当，并设置（）。