How Have Most Colleges and Universities Sought to Deal with Romantic

How have most colleges and universities sought to deal with romantic and sexual relationships between faculty and students?

A) Most prohibit all romantic and sexual relationships between members of these two groups.
B) Most tolerate other-gender relationships but not same-gender relationships.
C) Most aim to function in loco parentis and establish regulations accordingly.
D) Most prohibit relationships between professors and any students they supervise.