Teaching BPSC बिहार प्राथमिक (1 to 5) शिक्षक भर्ती 4.0 Mock Test General Knowledge Science Technology and Inventions
Spraying of D.D.T. on crops produces pollution of ________.
1
Air only
2
Air and soil only
3
Air, soil and water
4
More than one of the above
5
None of the above