4. A campaign manager wants to know whether a television advertisement will improve a candidate's vote share in the upcoming election. The campaign manager could use an experimental research design to test the effectiveness of the advertisement. A. The campaign manager wants to know about the effect of the television advertisement. What's the point of asking experiment participants what they think about the candidate after not showing them the advertisement? It sounds like a waste of money to the campaign manager. Explain how having a control group helps ical to evaluate the effect of the ad. B. The campaign manager wants to know if the experiment participants should be asked what they think about the candidate t of before they watch the advertisement (or they sit through the control condition). ingly Identify an advantage and a disadvantage of using a pretreatment measurement in sh an experiment like this