In Regard to the Most Favored Nation (MFN) Principle That

In regard to the Most Favored Nation (MFN) principle that is a key provision of the General Agreement on Tariffs and Trade (GATT) and World Trade Organization (WTO) trade law, what do GATT and the WTO say regarding the North American Free Trade Agreement (NAFTA) , a regional trading agreement?

A) NAFTA's terms are fully consistent with MFN
B) NAFTA is permitted as part of a deal among certain countries allowing other free trade agreements
C) NAFTA is allowed as an exception since it does not raise barriers against non-members
D) NAFTA provides MFN to non-member countries