Help the HR manager complete her slightly concerning hiring report by choosing the correct phrase.

The committee interviewed fifteen candidates for the dragon-tamer position, _____ had any actual experience with fire-breathing reptiles.

The correct answer is none of whom.

Because the two clauses are joined only by a comma, we must use a relative pronoun to create a non-defining relative clause. "None of them" would create a comma splice (two independent clauses improperly joined by a comma).

Furthermore, because the pronoun follows the preposition "of" and refers to people (candidates), we must use the objective case "whom" rather than "who" or "which."