天然橡胶的化学组成是[ ]

A．聚异戊二烯

B．聚乙烯

C．聚丙烯

D．戊烯

-Did Mrs Brown leave a message?

-Yes.  She wanted to know____this Sunday.

A．that you will go shopping

B．when will you go shopping with her

C．if you would go shopping with her

D．who you would go shopping