Recent reports of acid rains industrial cities are due to the effect of atmospheric pollution by:
a. Excessive release of NO2 and SO2 by burning of fossil fuels
b. Excessive release of CO2 by burning of fuel like wood and charcoal, cutting of forests and increased animal population
c. Excessive release of NH3 by industrial plants and coal gas
d. Excessive release of CO in atmosphere by incomplete combustion of cock, charcoal and other carbonaceous fuels in pancy of oxygen