How does edmonds fool the merchant in Louisville into believing that she is who she pretends to be (a foreigner with little knowledge of american politics)

She acts as though she does not know the difference between the Union and the Confederate sides.

Explanation:

Edmonds’s pretended ignorance makes the merchant believe that she is who she claims to be, and it leads him to let down his guard as he recruits her to help the Confederate cause.

the answer is a) to be able to obey them.