_______you can easily have lunch in the restaurant around the corner, why do you take the trouble to drive many miles here?

A．When

B．Unless

C．While

D．Where

主要用于厌氧菌感染的药物是

A．多西环素
B．庆大霉素
C．青霉素
D．环丙沙星
E．甲硝唑