— May I park my car here, Sir? 

—_________. You may park it over there.

A．Yes, you may

B．Yes, you can

C．No, you needn't

D．No, you mustn't

个体发育过程中最早产生的抗体是（）。

A.IgA

B.IgE

C.IgD

D.IgM

E.IgG