According to the New Trade Theory

According to the new trade theory

A) the ability to capture first-mover advantages is restricted in a world that disallows trade.
B) differences in labor productivity between nations underlie the notion of comparative advantage.
C) a country may predominate in the export of a good because it has firms that were among the first to produce that good.
D) to ensure economic progress,countries should implement several trade barriers.
E) different goods use resources in different proportions and this leads to constant returns to specialization.