Answer: CO 2 , CH 4 , N 2 O, and water vapour.
- A O<sub>2</sub> and N<sub>2</sub>, the most abundant atmospheric gases
- B CO<sub>2</sub>, CH<sub>4</sub>, N<sub>2</sub>O, and water vapour
- C O<sub>3</sub> and H<sub>2</sub>, released mainly from industrial combustion
- D SO<sub>2</sub> only, emitted from coal-burning power plants
Correct answer: B. CO<sub>2</sub>, CH<sub>4</sub>, N<sub>2</sub>O, and water vapour
Explanation: Main greenhouse gases: CO<sub>2</sub> (from fossil fuels, deforestation), CH<sub>4</sub> (from livestock, rice paddies, natural gas), N<sub>2</sub>O (from fertilizers), water vapour (most abundant), and CFCs. They trap heat by absorbing outgoing infrared radiation.
Sunlight passes through the atmosphere and warms the surface; the surface re-radiates this energy as infrared heat, which greenhouse gases (CO₂, CH₄, water vapour) absorb and trap - a naturally beneficial process that intensifies into global warming as gas concentrations rise from human activity.
Concept context
Pollution, global warming, ozone depletion, deforestation, and sustainability. Important for NEET and general awareness.