Which of the following best describes a market where a seller with market power would use the "hurdle method"? A) College students have a higher willingness to pay for textbooks than non-college students B) Some theater fans can't afford to pay full-price for Broadway shows, but they are willing to in line to purchase discount tickets C) People are willing to pay a higher price for human medicine than they are willing to pay for pet medicine D) People with higher incomes can afford to pay higher college tuition