I thought this might be a good one for today since Tuesday is election day here in the US. Two homophones, and a third word thrown in for good measure. While "decent" isn't pronounced the same as the other two, it is easily confused on the page. So I thought it was a good idea to include it here.
Decent (DEE-sent) – good, kind, caring
Descent (di-SENT) – moving downward
Dissent (di-SENT) – protest