In the United States, the Corporate Average Fleet Efficiency Standards

In the United States, the corporate average fleet efficiency standards require the fleet of

A) trucks produced by auto manufacturers each year to achieve lower rates of pollution.
B) planes produced by aircraft manufacturers each year to achieve lower rates of pollution.
C) buses produced by bus manufacturers each year to achieve a stated number of miles per gallon on average.
D) cars produced by auto manufacturers each year to achieve a stated number of miles per gallon on average.
E) trains produced by train manufacturers each year to achieve a stated number of miles per gallon on average.