Civil Services OPSC OAS Mock Test Series 2025 General Knowledge Ecology and Environment Environmental pollution
Which of the following gases is/are covered by the National Ambient Air Quality Standards?
1. Carbon Dioxide
2. Carbon Monoxide
3. Ozone
Select the correct answer using the code given below.
1
1 only
2
1 and 2 only
3
2 and 3 only
4
1, 2 and 3