---- You'd better_______ some popcorn or soft drinks before the film begins.

---- But I think it's better _______ anything while watching the film.

A．buy; not have

B．to buy; not to have

C．to buy; not have

D．buy; not to have

受地转偏向力影响，洪积扇横坡面呈现高度由一侧向另一侧递减的现象。