Traditional international economics

From the perspective of international economics, the basic unit or subject of economic activities is A. individuals B. enterprises C. groups D. countries.

A: At that time, the disciplines of traditional international economics such as comparative advantage and factor endowment theory were D; Nowadays, international economics is very chaotic, especially after 2 1 century. Since the emergence of heterogeneous enterprise theory, the research subject has a tendency to change to enterprises.