How did General Washington find the cannons he needed to attack the British in Boston?

A:A. He sent letters to colonial leaders begging them for cannons.
B:B. He sent Henry Knox to Fort Ticonderoga to bring cannons to Boston.
C:C. He sent Henry Knox to Canada to bring cannons to Boston.
D:D. He ordered the colonies to manufacture cannons for the army.

B. He sent Henry Knox to Fort Ticonderoga to bring cannons to Boston.