A group of researchers wants to know if watching comedy shows about the news makes people more or less knowledgeable about actual facts with regard to current events. They survey 5,000 people about what shows they typically watch, and also have them answer a series of questions about current events. They then analyze whether people who watch comedy news shows get more or fewer questions correct. What type of research design is this study? a) Case study b) Naturalistic observation c) Correlational d) Experimental