Sandra wants to purchase a Nitro scooter from the only Nitro dealer in town, but the dealer will not sell her the scooter unless she also purchases an extended warranty for $1,000. Sandra does not want to purchase the extended warranty from the dealer because she knows she can purchase the exact same warranty from her insurance company for $500. In this instance, the Nitro dealer appears to be violating one of the provisions of:
a. the Robinson-PatmanAct.
b. the Sherman Act.
c. the Federal Trade Commission Act.
d. the Clayton Act.