By the time my parents reached home yesterday, I _____ the dinner already.

A．had cooked

B．cooked

C．have cooked

D．was cooked

下列哪组配伍用药是合理的

A．青霉素+红霉素

B．庆大霉素+阿米卡星

C．庆大霉素+氨苄西林

D．阿米卡星+呋塞米

E．青霉素+四环素