A. World forest day
B. World environment day
C. World red cross day
D. World food day
Pollution
Pollution
A. Micro-organisms
B. Green vegetation of an area
C. Food crop
D. None of these
A. Population explosion
B. Nitrogen di-oxide
C. Global warming
D. Sulphur dioxide
A. Industrial wastes poured into water bodies
B. Extent to which water is polluted with organic compounds
C. Amount of carbon monoxide inseparably combined with haemoglobin
D. Amount of oxygen needed by green plants during night
A. Heavy metals
B. Faecal matter
C. Industrial effluents
D. Pollen of aquatic plants
A. Eichhornia crassipes
B. Solanum nigrum
C. Hydrilla
D. Parthenium hysterophorus
E. All of these
