Which agricultural innovation allowed maize cultivation to expand into higher altitudes in the Andes?

💡 Explanation

In the Andes, cooler temperatures limit maize growth. Terrace farming creates microclimates on sun-facing slopes that accumulate warmth, extending the growing season at high altitudes. Therefore terrace farming enabled high-altitude maize cultivation, rather than crop rotation, chinampas, or raised beds, which address nutrient deficiencies or water management.

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