The correct answer is B.
Gas rationing occurred during WWII in order to help control gasoline usage which was in short supply.
The U.S. Office of Price Administration issued a variety of stickers to identify users and control the amount of petrol used.
Some say that the gas rationing was done to conserve tires, as Japanese armies in the Far East cut America off their main supplies of rubber.
Gas rationing began on December 1, 1942 and ended on August 15, 1945. Speed limits were 35 MPH for the duration.