Final answer:
Corn, beans, and squash have been an important part of American cuisine for thousands of years. Native American agriculturalists grew these crops as the principal foods of their diet because they grew well together and provided a balanced and nutritious diet.
Step-by-step explanation:
The triad of corn, beans, and squash has been an important part of American cuisine for thousands of years. Native American agriculturalists grew these crops as the principal foods of their diet. The three foods grew well together, with the corn providing a support for the beans to climb and the large squash leaves providing shade and moisture retention. Additionally, the combination of corn, beans, and squash provides a balanced and nutritious diet, as corn provides carbohydrates, beans provide protein, and squash provides vitamins and minerals.