Final answer:
The Inca developed their farming techniques through terrace farming, which involved cutting out flat areas along the mountainside to create easily worked plots.
Step-by-step explanation:
The farming techniques used by the Inca developed through the use of terrace farming. Due to the steep mountains in the Andes, the Inca farmers created terraces by cutting out flat areas along the contours of the mountains, allowing for easily worked plots.
These terraces were built by creating retaining walls and filling them with loose stones for drainage, and then topping them with soil. Terrace farming provided the Inca with flat surfaces for growing crops in the mountainous terrain.