Billy: I’ve been fixing the computer for over three hours, but it still doesn’t work.

Nana: Why don’t you take a rest and try 　　　?  Maybe you’ll do better then.

A．early

B．finally

C．later

D．once

下列配伍中属于“十九畏”的药物是

A．大戟与甘草

B．贝母与乌头

C．乌头与瓜蒌

D．官桂与赤石脂

E．芍药与藜芦