给下列句子排序，构成正确的对话。

( ) Sure.

( ) I can sweep the floor and cook the meals.

( 1  ) Are you helpful at home?

( ) Great! You're helpful.

( ) What can you do?

不会导致叶酸缺乏的药物是（）

A.甲氨蝶呤

B.乙胺嘧啶

C.苯妥英钠

D.考来烯胺

E.肼屈嗪