Khadins, Bundhis, Ahars and Kattas are ancient structures that are examples for

Water harvesting is an age-old concept in India and is practiced in India from years. Khadin structures are practiced in Rajasthan for water harvesting, Bundhis in Madhya Pradesh and UttarPradesh, Ahars in Bihar and Kattas in Karnataka. These types of ancient structures are still used for water harvesting. So, option (c) is the correct answer.