Suppose That Government Wants a Policy That Will Encourage People

Suppose that government wants a policy that will encourage people to use less oil. For this policy to be efficient, it must:

A) induce those with the highest cost of conserving to reduce their oil consumption the most.
B) induce those with the lowest cost of conserving to reduce their oil consumption the most.
C) force everyone to reduce oil consumption equally.
D) force rich people to reduce oil consumption proportionally more than poor people.