Which sentence would be an effective thesis statement for a historical essay on the american industrial revolution?

the right answer for the question that is being asked and shown above is that: "their policy of "divide and rule" pitted political groups against each other to keep any one group from becoming too powerful.  " the  participant in european imperialism is being described below is that  their policy of "divide and rule" pitted political groups against each other to keep any one group from becoming too powerful. 

social contract theory, nearly as old as philosophy itself, is the view that persons' moral and/or political obligations are dependent upon a contract or agreement among them to form the society in which they live