Which of the Following Statements Is TRUE? I

Multiple Choice

Which of the following statements is TRUE? I. If a country does not trade, its knowledge is approximately equal to that used by one brain. II. The basic idea of trade is to buy the things that would cost you a lot to make, and sell the things that you can make at a low opportunity cost. III. Trade leads to specialization, which in turn increases in productivity.

A) II and III only
B) III only
C) II only
D) I, II, and III