Sherman's strategy of waging war throughout the south, not just on the battlefields, was called

The strategy being described is known as total war.

This strategy was used in Sherman’s March to the Sea. This military campaign by the Union Army revolves around completely destroying the South. This included actions such as destroying thousands of miles of railroad tracks and burning thousands of acres of crops. Both of these actions were meant to hurt the capabilities of the Confederate army.

The answer is option c.