The correct option is Shortughai.
Explanation
Most Harappan sites are located in semi-arid lands, where irrigation was likely required for agriculture. While water was drawn from wells and reservoirs in many regions, specific archaeological evidence for river-fed canal irrigation is rare and localized.Detailed Analysis:
- Shortughai (Correct): Located in Afghanistan, this Harappan outpost is the primary site where clear traces of ancient canals have been discovered. It is believed that water was diverted from nearby rivers (such as the Kokcha) to irrigate fields. However, similar evidence has not been found in the Punjab or Sindh regions, possibly because ancient canals there silted up or were destroyed by subsequent agricultural activity.
- Kalibangan: Located in Rajasthan, this site is famous for providing evidence of a ploughed field (early Harappan levels), showing a grid pattern of furrows, suggesting two crops were grown together. It does not have evidence of canals.
- Banawali: Located in Haryana, this site is known for the discovery of terracotta models of the plough, indicating the use of ploughs in agriculture, but not canals.
- Dholavira: Located in Gujarat (Rann of Kutch), this site is renowned for its sophisticated water harvesting system comprising massive reservoirs and dams to store water, rather than river-fed canals.
Key Takeaway:
Shortughai (Afghanistan) is the specific Harappan site noted for canal irrigation traces, whereas other sites are known for reservoirs (Dholavira), ploughed fields (Kalibangan), or plough models (Banawali).