If businessmen are taxed too much, they will no longer be motivated to work hard, with the result that government tax revenues might actually ______.

A．predictions
B．provisions
C．observations
D．preparations

A．The rate of killing has been accelerating.
B．The US government forbids imports of both raw and finished ivory.
C．They realized that the killing of elephants is a serious threat to their tourist business.
D．African people advocated an ivory ban.