Many experts seem to agree that _______ certain limit should be set on ________ consumption of cars to ease air pollution.

A．a; the

B．/; the

C．the; /

D．the; a

下列免疫细胞间的相互识别中，错误的是（）

A.LFA-3与CDl

B.CTLA-4与B7

C.CD28与B7

D.ICAM-1与LFA-1

E.CD4与MHCⅡ类分子