根据各组对话内容，从下面提供的5个选项中选出能填入空白处的最佳选项。

A:Could I use your dictionary, please

B:()

A:Thank you. I’ll return it as soon as possible.

A．Sure. What is it

B．It’s very nice of you to say so.

C．It’s nothing.

D．Have a nice trip!

E．Certainly, Here you are.

水溶性维生素中化学性质较稳定的是（）

A.维生素B₁

B.维生素B₂

C.维生素B₆

D.维生素C

E.维生素PP