All of the Following Are Required to Make a Tying

Multiple Choice

All of the following are required to make a tying arrangement vulnerable to antitrust prosecution except which one?

A) There must be some nontrivial amount of commerce affected by the tying contract.
B) There must be at least two products involved.
C) The seller cannot have substantial market power in the market for the tying product.
D) There must be proof of an actual tie between two products.