Answer:
With careful student pairings, academics would improve and new friendships would form.
Explanation:
Pathos is the appeal to emotions. Two of the sentences really appeal to the readers' emotions. The sentence about student pairings and the sentence about families complaining. The question though asks which uses pathos to support the claim that "A student tutoring program should be established so that peers can help one another." The last sentence about families complaining does not directly support the claim that peers can help one another. The cost benefit of a student-run program is just a side benefit.
I think it is an informal idiom
