How did Indus River Valley civilizations use irrigation techniques?

Farmers used irrigation to protect fields from land overuse.
Farmers used irrigation to offset flooding and protect crops.
Famers used irrigation to manage the water supply for crops.
Famers used irrigation to create land for better roads and houses.

The correct answer is the third statement.

Explanation:

This is because the first and last statements are completely incorrect as irrigation systems had to do with routing water from streams and lakes, into farms in order to hydrate plants. The second answer is technically correct in my opinion, because once flood season came farmers used irrigation lines to re-route water to reservoirs or other places besides their farms. Although, this was not the main purpose of irrigation systems.

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