In a Perfectly-Competitive World, Restrictions Placed by Developing Countries to Halt

Multiple Choice

In a perfectly-competitive world, restrictions placed by developing countries to halt a "brain drain" would lead to __________ in efficiency and world output in a static sense;Over time, these restrictions might, other things equal, __________ in the per capita income differences between developing countries and developed countries if skilled labor has important production externalities.

A) a decrease; lead to an increase
B) a decrease; also lead to a decrease
C) an increase; lead to a decrease
D) an increase; also lead to an increase