Which of the Following Statements About Comparative Advantage Are True

Which of the following statements about comparative advantage are true?
1) A country's pattern of comparative advantage depends partly upon the relative abundance of different types of resources in its endowment of factors.
2) Trade allows small countries to reap economies of scale through specialization.
3) Climate affects a country's pattern of comparative advantage.

A) 1 and 2
B) 2 and 3
C) 1,2,and 3
D) 1 only
E) 2 only