Why Does the Proliferation of Regional Trade Agreements (RTAs)encourage Optimism

Why does the proliferation of regional trade agreements (RTAs) encourage optimism about the reduction of human rights abuses?

A) The ease of travel across borders makes it easier to flee abusive governments.
B) Prosperity from trade leads to the elimination of human rights abuses.
C) Members of RTAs enforce human rights provisions in other member countries.
D) Nearly all trade agreements include provisions on human rights.