Why did some northerners in congress disapprove of the kansas-nebraska act?

Plsss 10 a candidate running for state governor has an ad on tv. the ad begins with a statement from the candidate about his or her commitment to improve the state, and then shows short interviews with average citizens who describe the candidate as the better choice for improving the state's economy. the ad goes on to display quotes from the opposing candidate printed over a backdrop of closed factories and charts of negative economic statistics. the statistics are associated with the opponent’s political party. what part of the ad uses symbolism to get the candidate's message across? the interviews with average citizens the images of closed factories the statement from the candidate about job programs the quotes from the opposing candidate