Who or whom in resume bullet

I've read the other posts outlining usage of who vs. whom, but I can't seem to apply them to this sentence (or rather bullet point on a resume). Should I be using who or whom (or something else entirely) here?

Established X Department summer intern program and led recruitment efforts to hire the group’s first intern, whom I trained, supervised, and mentored

I would appreciate any help you can provide.

Answer

Correct! Direct object (objective case) of the verbs.