Dr Pow Is Interested in Whether Exposure to TV Advertisements

Dr. Pow is interested in whether exposure to TV advertisements has a different impact on girls' self-image than it does on boys' self-image. To examine this question, she conducts a quasi-experiment. Why doesn't Dr. Pow conduct a true experiment instead?

A) She cannot conduct a true experiment, because people cannot be randomly assigned to be "girls" or "boys."
B) She cannot conduct a true experiment, because self-image is not directly observable.
C) She could conduct a true experiment if she wanted to, but she probably has a very small sample size, so in this case a quasi-experiment is better.
D) She could conduct a true experiment if she wanted to, but she is probably interested in "real-life" TV exposure (and probably doesn't want to manipulate this variable) .