Ceramic Customs Co. requires a specific type of ceramic to make custom-made tiles. Since only one supplier makes that particular ceramic, the firm is forced to source all of its supplies from it. The firm tried negotiating the price at which it purchases the material, but failed to get any reduction on the cost. This is because: a. the supply exceeds the demand. b. the industry has barriers to entry c. the supplier has more bargaining power than the firm. d. the supply is unlimited.