Consider a Shoemaker and a Vegetable Farmer

Consider a shoemaker and a vegetable farmer.Potentially,trade could benefit both individuals if

A) the shoemaker can produce only shoes and the vegetable farmer can produce only vegetables.
B) the shoemaker is capable of growing vegetables, but he is not very good at it.
C) the vegetable farmer is better at growing vegetables and better at making shoes than the shoemaker.
D) All of the above are correct.