Correct Answer - Option 1 : 1, 3 and 4
Explanation:
Emission from petrol engines contains a greater concentration of HC, CO2, and CO while the four-stroke diesel engines (buses and trucks) contain a greater concentration of NOx in addition to thick smoke and particulate matter.
AIR POLLUTANTS can be broadly classified into two general groups -
- A primary pollutant is an air pollutant emitted directly from a source. Eg. Particulates, COx, SOx, NOx, Bacteria, Fog, Soot, Dew, etc
- A secondary pollutant is not directly emitted as such, but forms when other pollutants (primary pollutants) react in the atmosphere. Eg. Ozone, PAN, PBN, PPN, Smog, CFC, and Acid Rain