The accomplishment which George Washington achieved was that, "He served as commander of the Continental Army."
Who was George Washington?
George Washington was the first president of the United States from 1789 to 1797. Continental Congress appointed him as a commander of the Continental Army. During the American Revolution, this Continental army was led by George Washington who got victory over the British and secured the independence of the United States.
George Washington served as the president of the Constitutional Convention of 1787. As a president he contributed to the creation the Constitution of the United States and the American federal government.
George Washington stood for individual liberty, national freedom, and protection of individual rights and he so wanted to create a strong central government which would serve to protect the liberties, the individual rights and freedom of its citizens.
Hence, option D is correct.
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