Which of the following are some important pollutants released by steel industry in India? 1. Oxides of sulphur 2. Oxides of nitrogen 3. Carbon monoxide 4. Carbon dioxide Select the correct answer using the code given below.

The steel industry is one of the most energy-intensive and polluting industries globally. Its production processes involve high temperatures and the combustion of various fuels (like coal and coke), leading to the release of a wide range of pollutants into the atmosphere.

1. Oxides of sulphur (SOx): These are released primarily from the combustion of sulfur-containing fossil fuels (like coal and coke) used in steel production.
2. Oxides of nitrogen (NOx): These are formed at high temperatures during the combustion processes in blast furnaces, coke ovens, and other steel-making units.
3. Carbon monoxide (CO): This toxic gas is produced due to incomplete combustion of carbon-based fuels in various stages of steel manufacturing.
4. Carbon dioxide (CO2): The steel industry is a major emitter of CO2, both from the combustion of fossil fuels for energy and from the chemical reactions involved in reducing iron ore (e.g., in blast furnaces where coke reacts with iron oxides to produce iron and CO2). Therefore, all four listed pollutants are significant emissions from the steel industry in India and globally.