Mary makes 10 pies and 20 cakes a day and her opportunity cost of producing a cake is 2 pies. Tim makes 20 pies and 10 cakes a day and his opportunity cost of producing a cake is 4 pies. If Mary and Tim specialize in producing the good in which each has a comparative advantage, ______.

A. Mary produces only pies B. Tim produces both pies and cakes C. Mary produces only cakes while Tim produces only pies D. Tim produces only cakes while Mary produces only pies Study Plan Problems and Applications