Which of these is likely to increase the supply of vanilla ice cream?

A) An increase in the price of vanilla beans,an ingredient in ice cream
B) A decrease in the sales tax on ice cream
C) An increase in the price of chocolate ice cream
D) A decrease in the price of milk,an ingredient in ice cream
E) An increase in the price of hot fudge

A decrease in the price of milk, an ingredient in ice cream, will lower the cost of production for vanilla ice cream and encourage producers to increase supply. An increase in the price of vanilla beans (A) would likely decrease the supply of vanilla ice cream, as it would increase the cost of production. A decrease in the sales tax on ice cream (B) may increase demand for ice cream, but it would not directly affect the supply. An increase in the price of chocolate ice cream (C) would not directly affect the supply of vanilla ice cream, as they are different products. An increase in the price of hot fudge (E) would not directly affect the supply of vanilla ice cream, as hot fudge is a complementary good but not an ingredient in the ice cream itself.