Which of the Following Is Not a Situation Under Which

Which of the following is not a situation under which men and women may be paid different wages under the Equal Pay Act?

A) When the differential is based on any factor other than sex.
B) When payment is made pursuant to a seniority system.
C) When the parties sign a waiver.
D) When payment is made pursuant to a merit system.
E) When payment is made pursuant to a system which measures earnings by quantity or quality of production.