The correct answer is the following.
Political machines contributed to urban political corruption by wasting tax paper money and getting rich in the process, and by placing unqualified people in government offices.
Political machines are political organization led by a powerful man or a small group of powerful people. They want to control the city or the state, "selling solutions" to people. The Tammy Hall organization, led by William Magear Tweed, is the best example of political machines in the U.S.
These political machines promise help and solutions to people's needs in exchange for a vote. It could be the promise of more jobs or better health care. Political machines harm people and contribute to urban political corruption by wasting tax paper money and getting rich in the process, and by placing unqualified people in government offices.