What final action made the independence of the United States a reality

What final action made the independence of the United States a reality?

A) the signing of the Treaty of Paris in 1783 between Great Britain and the United States ending hostilities and settling boundaries, fishing rights, and legal claims
B) the signing of separate treaties of Britain with France and Spain in 1783 to resolve respective territorial and legal claims
C) the withdrawal of British troops from New York City, Charlestown, and Savannah in 1780
D) a political change in the British government that permitted the ratification of the Treaty of Paris by a reluctant Parliament

ANSWER
Answer: A