—"I'm sorry I forgot _____ the letter for you!"

—"It doesn't matter, I'll post it myself." [ ]

A. to post

B. posting

C. post

D. posted

深交所规定申购单位为( )股，每一证券账户申购数量不少于( )股。

A．100；100
B．100；500
C．500；1000
D．500；500