Answer :
Answer:
A. A terrace
Explanation:
A terrace would be a great help for the farmer.
Final answer:
Terracing would be the most useful Inca advancement for a farmer living on the edge of a steep mountain to increase crop production.
Explanation:
If a farmer living on the edge of a steep mountain wants to increase the amount of crops he can grow, the most useful Inca advancement for him would be a terrace. Terracing is a farming technique used by the Incas to create flat steps on a mountain slope. It helps prevent erosion, retain water, and provide more arable land for cultivation. By building terraces, the farmer can expand his farming area and improve crop production.
Learn more about Inca advancements for agriculture here:
https://brainly.com/question/15314623
