The correct option is C (i), (ii) and (iv)
Both sulphur and nitrogen oxides are major air pollutants. They are released by the burning of fossil fuels. Nitrogen oxides are mostly released by the combustion of fossil fuels in vehicles, especially diesel powered vehicles and power plants. Similar to sulphur oxides, nitrogen oxides can also combine with moisture to form nitric acid that can precipitate as acid rain. Smog is formed when nitrogen oxides and volatile organic compounds react in the presence of heat and sunlight. One of the major health implications of sulphur and nitrogen oxides is asthma.