Checks and Balances, sorry comment if this is wrong.
Answer: What was the result of the Philadelphia convention in 1787?
The result of the convention was the creation of the Constitution of the United States, placing the Convention among the most significant events in American history. The convention took place in the old Pennsylvania State House (now known as Independence Hall) in Philadelphia.
Explanation: an educated guess
I would say either A or C, but i'm not positive, my research didn't tell me much, sorry!