Assume that El Salvador can generate coffee at lower opportunity costs than Spain, whereas Spain can generate olive oil at lower opportunity costs than El Salvador. The citizens of both countries can potentially profit from international trade since of the efficiency related with: (1) Positive economics. (2) Comparative advantage. (3) The circular flow model. (4) Diminishing returns. (5) Normative economics.
Can someone please help me in finding out the right answer of the above question.