Answer:
A. "The Dallas Cowboys, who wore blue, were the worst football team in the league."
Explanation:
Nonessential clauses are phrases within a sentence that are unnecessary and only provide additional information; however, the sentence could still work without the clause.
Identifying Nonessential Clauses
One of the best ways to identify a nonessential clause is to take it out of the sentence. If the sentence still makes sense, the clause was nonessential.
For example, the sentence, "The Dallas Cowboys were the worst football team in the league," still makes sense. You only lose a little information that was not needed to understand the sentence.
Comma Rules
Nonessential clauses are also known as interrupters. All interrupters need to be offset by commas. This means that there must be a comma before and after the interrupter. The only exception to this rule is if the interrupter is at the end of the sentence, so the period replaces the comma.
For example, "The movie had a great action scene, which was my favorite part." In this sentence, the interrupter is at the end, so there is only one comma.
We can use this information to answer this question. Only answer choice A has the clause offset by commas, so this clause must be nonessential.
