Answer: Possessive error: opinions' should be changed to opinions.
The newspaper article discussed several senators’ opinions about how to balance the budget.
Explanation:
Because opinions' would mean that the senators' opinions would possess something of their own, and the opinions do not seem to possess something in the sentence, opinions' should be changed to opinions.
Correct:
The newspaper article discussed several senators’ opinions about how to balance the budget.
Correct:
The senators' opinions' effects on the city were not very positive and resulted in multiple disputes.
Incorrect:
The newspaper article discussed several senators’ opinions’ about how to balance the budget.
I hope this helps!