The Kaveri Delta region is known for its extensive network of:

Irrigation canals
Rainwater harvesting structures
Groundwater wells
Desalination plants

The correct answer is: a) Irrigation canals.

The Kaveri Delta region is a vast area of land in southern India that is home to millions of people. The region is known for its rich agricultural land, which is made possible by the extensive network of irrigation canals that crisscross the area. The canals are fed by the Kaveri River, which is one of the most important rivers in India. The irrigation canals provide water for crops, as well as for drinking and other domestic purposes.

The other options are incorrect because:

  • Rainwater harvesting structures are not as common in the Kaveri Delta region as irrigation canals.
  • Groundwater wells are not as extensive as irrigation canals.
  • Desalination plants are not used in the Kaveri Delta region.