The answer is "A", "They benefited from the trade networks".
A trade network is an arrangement of individuals in various terrains who exchange products forward and backward. Trade includes the exchange of merchandise or administrations starting with one individual or element then onto the next, regularly in return for cash. A framework or system that permits trade is known as a market. An early type of trade, barter, saw the immediate trade of merchandise and enterprises for different products and ventures.
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Answer:
The Vietnam War was a long, costly and divisive conflict that pitted the communist government of North Vietnam against South Vietnam and its principal ally, the United State.