Final answer:
The British capture of Philadelphia in September 1777 was thought by the British to potentially end the war, but it did not achieve that goal. The correct option is 3.
Step-by-step explanation:
The British thought that the capture of Philadelphia, the home of the Continental Congress in September 1777, would end the war. General Howe brought fifteen thousand British troops to Chesapeake Bay as part of his plan to take Philadelphia.
After defeating Washington's soldiers in the Battle of Brandywine Creek, the British took control of Philadelphia, which made the Continental Congress flee from the city.
However, this did not end the war as the British had hoped. The effort to isolate New England failed with the British surrender at Saratoga in the fall of 1777, which later brought France into the war in support of the American cause.The correct option is 3.