Question

complete the sentence with the best relative pronoun. thats sergeant dawson, jacob served with in the army.

Explanation:

The sentence is a non - restrictive relative clause (indicated by the comma) referring to a person (Sergeant Dawson) and the relative pronoun is the object of the preposition "with". For people, when used as an object in a non - restrictive relative clause, "whom" is the appropriate relative pronoun. "Who" is used as a subject, "which" is for things, and "that" is not used in non - restrictive relative clauses.

Answer:

whom