Solve the linear programming problem. A doctor has told a patient to take vitamin pills. The patient needs at least 12 units of vitamin A and at least 8 units of vitamin D. The red vitamin pills cost 20 each and contain 3 units of A and 1 unit of D. The blue vitamin pills cost 354 each and contain 2 units of A and 2 units of D. To avoid indigestion, the patient should take no more than 6 red pills and no more than 9 blue pills. How many pills should the patient take each day to minimize costs? . .. O A. 2 red and 3 blue O B. 0 red and 9 blue O C. 6 red and 9 blue O D. 6 red and 1 blue