Which one of the following chemicals has been banned in India?

DDT

The correct answer is option 4. DDT.

DDT was discovered to be quite effective during World War II in preventing malaria and other insect-borne illnesses. So, following the war, DDT was employed in agriculture to reduce the harm that insects, rodents, weeds, and many crop diseases caused. However, its usage has been banned in India due to adverse effects.