Final answer:
The correct answer is option O.
Step-by-step explanation:
The correct answer is:
O Known as the leading portraitist of America's Federal period, Gilbert Stuart (1775-1828) produced more than a thousand portraits of four presidents, diplomats, and notables he was best known for his portraits of George Washington.
This answer is correct because it does not contain a comma splice or a fused sentence. It is a grammatically correct sentence that clearly states the subject and verb.
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