Traditional water harvesting structures used in Telangana include:

The correct answer is: D) All of the above

Tanks, check dams, and wells are all traditional water harvesting structures used in Telangana.

• Tanks are artificial reservoirs that are used to store rainwater. They are typically built on hilltops or in valleys, and they can be used for irrigation, drinking water, and fish farming.
• Check dams are small dams that are built across streams or rivers. They are used to slow down the flow of water, which allows more time for the water to soak into the ground.
• Wells are holes that are dug into the ground to reach groundwater. They are used for drinking water, irrigation, and industrial purposes.

Traditional water harvesting structures are important because they help to conserve water during periods of drought. They also help to improve the quality of water by filtering out pollutants.