Answer:
C.
Step-by-step explanation:
In the context of the General Agreement on Tariffs and Trade (GATT), free trade areas and customs unions were seen as exceptions to the most-favored-nation (MFN) principle, which states that countries should not discriminate between their trading partners. Free trade areas and customs unions involve preferential treatment among member countries, which goes against the MFN principle.
However, the contracting parties to the GATT allowed for the creation of free trade areas and customs unions as long as they promoted trade and economic integration among member countries. These exceptions were made in recognition of the potential benefits that such arrangements could bring.
Therefore, option C accurately describes the stance on free trade areas and customs unions in relation to the GATT.