Solution:David Ricardo (1817) -Theory of comparative advantage
Michael porter (1990)- Theory of competitive advantage.
Adam Smith (1776)- Theory of absolute advantage. According to this theory every country will be specialized in producing a product in which it has more advantage than other country.
Heckscher (1919 - ohlin (1933)- Factor Of Endowment Theory
According to this theory, A nation will export the commodity whose production requires the intensive use of the nation's relatively abundant and cheap factor and import the commodity whose production requires the intensive use of the nation's relatively scare and expensive factor.