Final answer:
The fact that some British reinforcements were arriving in New York as the Declaration was being signed best supports the statement that some of the effects of the Declaration of Independence were bitter.
Step-by-step explanation:
The fact that best supports the statement that some of the effects of the Declaration of Independence were bitter is that British reinforcements were arriving in New York as the Declaration was being signed. This fact shows that the colonists were facing immediate military opposition and the British intended to suppress their bid for independence.
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