trade blocs help countries by\nlimiting competition.\nincreasing barriers to trade.\nimproving product…

Answer:

D. allowing the pooling of resources.

Brief Explanation:

Trade blocs enable countries to combine resources, which can lead to economic benefits like cost - sharing and increased efficiency. Limiting competition and increasing trade barriers are generally negative aspects not associated with the positive role of trade blocs. While improving product production can be a result, pooling resources is a more fundamental advantage.