Teaching BPSC 4.0 बिहार उच्च माध्यमिक शिक्षक भर्ती (PGT) Mock Test General Knowledge Ecology and Environment Conservation efforts: India and World
Why have developed countries put ban on DDT a pesticide?
1
Quality of soil was decreasing
2
Soil erosion was increasing
3
It was affecting food-chain system
4
More than one of the above
5
None of the above