能直接杀伤肿瘤细胞的是（）

A.NK细胞

B.B细胞

C.CD8⁺T细胞

D.CD4⁺T细胞

E.树突细胞

—Could you please tell me something about your travel in Sydney?      

— _______!

A．Excuse me.

B．It’s very nice of you to say so.

C．Certainly, I’ll be glad to.

D．No, I don’t like it.