Classic Jeans has informed its retailers that they must either sell its new line of jeans for $39.99 or no longer be supplied by Classic Jeans. The retailers agree to this. Classic Jeans and its retailers are involved in:
a. violation of the Wheeler-Lea Act.
b. horizontal price fixing.
c. violation of the Lanham Act.
d. vertical price fixing.
e. an attempt to maximize profits.
Answer: D