What Is One of the Most Common Problems That Students

What is one of the most common problems that students face in identifying a research topic?

A) Asking a research question that is not important (e.g., Do children with learning disorders study better in a blue room as compared to a yellow room?)
B) Asking a research question that requires an experimental design (e.g., How does rap music influence children's aggressive behavior?)
C) Asking a research question that has already been established (e.g., Is interparental conflict harmful to children?)
D) Asking a research question that is too large (e.g., What therapy is most effective?)