Techno, Inc., sells its brand-name computer equipment directly to its franchised retailers. Depending on how existing franchisees do, Techno may limit the number of franchisees in a given area to reduce intrabrand competition. Techno’s restrictions on the number of dealers is

a. a per se violation of the Sherman Act.

b. exempt from the antitrust laws.

c. subject to continuing review by the appropriate federal agency.

d. subject to the rule of reason.