After the Battle of Bunker Hill, General Howe and the British A. left Boston seeing Washington's reinforcements. B. regrouped after losing the hill. C. celebrated their clear victory. D. forced Washington out of Massachusetts.

I think its A (left Boston seeing Washington's reinforcements)

The correct option is A.

The battle of Bunker Hill is one of the earliest battle of American revolution. The battle was between the British and the colonists. The British won the battle and take over Boston, but they were forced to leave when they saw the reinforcement from Washington, which was requested for by the colonists.