Serene Dairy has four product lines: sour cream, ice cream, yogurt, and butter. The total cost of producing the milk base for the products is $45,000, which has been allocated based on the gallons of milk base used by each product. Results for July follow: Sour Cream Ice Cream Yogurt Butter Total Units sold 2.000 500 400 2.000 4.900 Revenue $10.000 $20,000 $10,000 $20,000 $60,000 Variable departmental costs 6,000 13,000 4,200 4,800 28.000 Fixed costs 5.000 2.000 3.000 7.000 17.000 Net Income (loss) 5.(1.000) $5.000 $ 2.800 5.8.200 $15.000 How much are total joint costs of the products? O A $28,000 OB. $15,000 O C. $17,000 O D. $45,000