Which sentence is correct? a. the tax cuts effect schools more than city services. b. the tax cuts affect schools more then city services. c. the tax cuts impact schools more than city services. d. the tax cuts have a greater impact on schools than on city services?

I believe the answer is: The tax cuts have a greater impact on schools than on city services.
For comparison like this, the usage of 'more' is considered to be appropriate compared to 'than on'
Since the word 'affect' is less formal compared to impact when used in economic term like this, option C is the right answer.