Write a history paper based on the underground railroad.  

This is my thesis statement that I came up with:

The Underground Railroad had spurred as a result of the Fugitive Slave Act, a sordid slavery system, and racial intolerance; the participants and fugitive slaves alike initiated slave rebellions, escaped via Underground Railroads, and took risks for fleeing as their act of resistance.

However the feedback I received was that its needs some clarification and improvement. My professor stated that I  should have 3 clear claims on why the Underground Railroad was an act of resistance.  The example below is a sample outline of how my thesis statement should be.

The Underground Railroad was an act of resistance because of ____________, ____________, and __________.  (You may need to modify this somewhat to ensure it makes sense.)  In the thesis below, it seems like you are arguing more than 3 claims.