4. The difference between, or the relationship between, the Rule of Reason and per se illegality in antitrust cases is: a. The Rule of Reason only existed before 2001, whereas per se illegality existed only after 2001 b. The Rule of Reason illegality applies only to deceptive advertising, whereas per se illegality applies only to involuntary restraints of trade c. Per se illegality applies only to deceptive advertising, whereas Rule of Reason illegality applies only to involuntary restraints of trade d. The Rule of Reason and per se illegality both exist today, but the Rule of Reason analyzes potentially anticompetitive actions that do not fit neatly into the per se category Antitrust law in the United States is a common law doctrine established without statute. T/F 5. 6. The Leegin Creative Leather case proved that there is no difference between interbrand and intra-brand competition in antitrust cases. T/F