In the cities of our country, which among the following atmospheric gases are normally considered in calculating the value of Air Quality Index?<br/>1. Carbon dioxide<br/>2. Carbon monoxide<br/>3. Nitrogen dioxide<br/>4. Sulfur dioxide<br/>5. Methane<br/><br/>Select the correct answer using the code given below.

1. Carbon dioxide — Not a standard pollutant in India’s Air Quality Index. AQI tracks health-relevant ambient pollutants, not CO2. Verdict: Incorrect.

2. Carbon monoxide — Included in National Air Quality Index. Verdict: Correct.

3. Nitrogen dioxide — Included in AQI as NO2. Verdict: Correct.

4. Sulfur dioxide — Included in AQI as SO2. Verdict: Correct.

5. Methane — Not included in India’s AQI. Verdict: Incorrect.

India’s AQI normally considers pollutants such as PM10, PM2.5, NO2, SO2, CO, O3, NH3 and Pb. Hence, only 2, 3 and 4 are correct.