A psychology student is curious about whether watching television will lead to lower grades. She decides to track her roommate's TV watching behavior across the entire school year, noting how much her roommate watches every day. She also finds out her roommate's grades on every exam she takes during the year, so that she can evaluate how the roommate's academic performance matches up with her TV viewing. She also asks her roommate questions about her classes, TV watching, and overall preparation. What type of research design is this study? a) Case study
b) Naturalistic observation
c) Correlational
d) Experimental