Behind the tractor rolled the shining disks, cutting the earth with blades not powering but surgery pushing the cut earth to the right where the second row of disks cut it .. which word or words most creates a negative tone toward the tractor? a. plowing b. to the right c. surgery d. second row

I would choose "surgery" here. The word "surgery" implies that the tractor is cutting the earth mechanically or inorganically. Surgery, in the most common sense, is a medical procedure which cuts open and probes one's body to correct a medical issue. If we apply this word to the "earth" it becomes somewhat nefarious. In short, "surgery" is an unnatural term here which implies the tractors displacement atop the earth. 
I hope this helps. If not, ask for clarification!  

Ithink your answer is b