The correct answer is D. Terrace farming
Step-by-step explanation:
The Incas were a Pre-Columbian civilization that began in Peru but covered other zones in Ecuador, Colombia, Bolivia, Chile, and Argentina. This civilization was mainly located in the Andes which is the most important mountainous range in South America. Due to this, the Incas depended on terrace farming (creation of terraces or flat platforms in hills or mountains) to grew crops as traditional techniques for agriculture did not work in this mountainous terrain. Thus, Incan agricultural success would not be possible without terrace farming.