Answer :
2 seems like the best answer because "b/c we saw some old friends" is modifying the verb of "left dinner"
Answer:
Your answer would be that the sentence with a clause used as a modifier to the verb is sentence 2.
Explanation:
Sentence 2 contains an adverb clause modifying the verb. Adverb clauses, also called adverbial clauses, are dependent clauses that function as adverbs. As they are dependent clauses, they must have a subordinating conjunction to connect them to the rest of the sentence. In this case, the subordinating conjunction introducing the adverbial clause is because. It gives us information as regars the cause of a particular action (leaving dinner) and modifies the verb "left".