--I think our school’s selective courses are of great use and I have learnt a lot from them.

--Yes _______.

A．No problem

B．I couldn’t agree with you more

C．I don’t think so

D．It doesn’t matter

下述氨基酸中除哪种外，都是生糖氨基酸（）。

A.天冬氨酸

B.苯丙氨酸

C.亮氨酸

D.异亮氨酸

E.精氨酸