-Do you like the city life or the country life?

-It's hard to say. In the city there are ________ interesting things, but in the country there is ________ pollution.[ ]

A. less; more

B. more; less

C. more; fewer

D.  much; much

暂时冠的作用不是（）

A.避免牙髓再度受刺激

B.保持患牙的牙位

C.避免（牙合）面磨损

D.保持近、远中间隙

E.为戴冠提供便利