College students are often recruited for research studies of young adult development, but this is often discussed as a limitation of those studies. How do you explain this?

A) university students tend to have higher rates of attrition compared to non-university students.

B) it is an ethical violation to recruit college and university participants without their parents consent.

C) it is more difficult to get IRB approval for studies involving college and university students.

D) college students are not randomly selected from the larger population, and they may not represent all young adults in our society.