Suppose That the Country of Xenophobia Chose to Isolate Itself

Multiple Choice

Suppose that the country of Xenophobia chose to isolate itself from the rest of the world. Its ruler proclaimed that Xenophobia should become self-sufficient, and so would not engage in foreign trade. From an economic perspective, when would this idea make sense?

A) If Xenophobia had an absolute advantage in all goods.
B) If Xenophobia had no absolute advantages in any goods.
C) Never as long as Xenophobia had a comparative advantage in any good.
D) Never as long as Xenophobia had an absolute advantage in at least half the goods traded.