Question

most americans have heard of paul revere. he is famous for riding through the night to warn that the british were coming. however, almost no one has heard of sybil ludington. ludingtons father, henry ludington, was an officer in the army during the revolutionary war. when british soldiers attacked a nearby town, a man rode to ludingtons house to warn him. henry had to prepare for battle, and the rider was too tired to continue. so sixteen - year - old sybil rode forty miles to tell her fathers men to gather for battle. she rode a longer distance than revere and was later thanked by george washington.
what is the main, or central, idea of the passage?
george washington thanked sybil ludington for her brave actions.
sybil ludington was only sixteen years old when she warned people about the british.
sybil ludington is not very well known, but she was just as brave as paul revere.

Explanation:

The passage first mentions Paul Revere's fame, then introduces Sybil Ludington. It details her act of riding a long distance (longer than Revere) to warn for battle. The key is to compare her (less - known) with Revere and highlight her bravery. The first two options are details (Washington's thanks and her age) not the central idea. The third option encompasses the comparison (not well - known vs Revere's fame) and her bravery (similar to Revere as she also rode to warn).

Answer:

Sybil Ludington is not very well known, but she was just as brave as Paul Revere.