Final answer:
The Third Estate comprised ninety-eight percent of the population in France and included peasants and impoverished nobility, but not parish priests.
Step-by-step explanation:
The Third Estate refers to the commoners or the working class in France during the Ancien Régime. They were the largest and most diverse social group, comprising about ninety-eight percent of the population. The group that was exclusively part of the Third Estate included peasants, who were the rural laborers and farmers, and the impoverished nobility, who were noble families that had fallen into poverty. However, parish priests of common descent were not part of the Third Estate as they were considered part of the clergy, which formed a separate estate.
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