—Don’t you think there are too many cars in our city?          

—I really think so. If there are    ___  people driving, there will be   ___    pollution.[ ]

A. less; less      

B. fewer; fewer      

C. less; fewer      

D. fewer; less

产生促胃液素(胃泌素)的细胞是

A．孕激素
B．人绒毛膜促性腺激素
C．雄激素
D．促性腺激素释放激素
E．促卵泡激素释放蛋白