Since Mayor Drabble always repays her political debts as soon as possible, she will almost certainly appoint Lee to be the new head of the arts commission. Lee has wanted that job for a long time, and Drabble owes Lee a lot for his support in the last election. Which one of the following is an assumption on which the argument depends? ['There is no one to whom Mayor Drabble owes a greater political debt for support in the last election than the political debt she owes to Lee.', "Whether Lee is qualified to head the arts commission is irrelevant to Mayor Drabble's decision.", 'Lee is the only person to whom Mayor Drabble owes a political debt who would be willing to accept an appointment from her as the new head of the arts commission.', 'Mayor Drabble has no political debt that is both of longer standing than the one she owes to Lee and could as suitably be repaid by an appointment to be the new head of the arts commission.']