利福平的抗菌作用机制是

A．抑制细菌分枝菌酸的合成
B．抑制细菌叶酸的合成
C．抑制细菌DNA螺旋酶
D．抑制细菌依赖于DNA的RNA多聚酶
E．抑制细菌蛋白质的合成

— Jack can't concentrate on his lessons recently.

— Yes, that might ____ why he did so badly in the last test.

A. answer for

B. apply for

C. account for

D. call for