What is the potential purpose of the water reservoirs found in Dholavira?

Water storage for agriculture

The correct answer is Option 4 - Water storage for agriculture

Given that most Harappan sites are situated in semi-arid regions, irrigation was likely necessary for agriculture. While traces of canals have been found at the Harappan site of Shortughai in Afghanistan, no such evidence has been discovered in Punjab or Sind. It is plausible that ancient canals have silted up over time. Moreover, it is probable that wells were used to draw water for irrigation purposes. Notably, water reservoirs found in Dholavira may have served as storage for agricultural water needs.