Which One of the Following Cases Is NOT an Example

Which one of the following cases is NOT an example of price discrimination?

A) Airlines charge different fares for business people than tourist travelers.
B) Young males are charged higher premiums for car insurance than older males or women.
C) A local phone company charges different telephone rates to residential and business users.
D) Electric companies charge different rates to commercial and residential users for electricity.
E) Theatres charge different rates for different age groups.