Correct option is D
Tamil Nadu was the first state in India to make rainwater harvesting compulsory for all buildings (both residential and commercial) in 2001. This step was taken in response to a severe water crisis and depleting groundwater levels. Rainwater harvesting systems ensure that rainwater is collected and stored, either for direct use or to recharge groundwater. Tamil Nadu’s initiative has since been adopted by other states as well. The practice has led to a significant improvement in groundwater levels and has become a model for water conservation efforts across India.
