I had uploaded the answer on the image.(I couldn't submit the answer as it was showing an error.
They had ancient sacrifices.
"Gerbils’ teeth grow continuously; therefore, gerbils need to chew daily to keep their teeth short."
The correct answer is 1, because the appositive there is 'the cardinal'. An appositive is usually separated from the rest of the sentence by commas, and refers to the subject.