Excuse me, could you tell me________?

A．where can I have my MP4 repaired

B．what was happened to you

C．how could I go to the e-shop

D．what is wrong with your bike

违背毒物使用原则的是（）。

A.使用时应了解其特性

B.不准用手直接拿取毒物

C.未用完的剧毒品应倒入下水道

D.剧毒品应由专人保管