Answer: compressed natural gas (CNG).
- A high-sulphur diesel oil
- B leaded motor petrol
- C compressed natural gas (CNG)
- D powdered bituminous coal
Correct answer: C. compressed natural gas (CNG)
Explanation: Delhi switched its buses and other public transport to compressed natural gas (CNG), which burns more completely and releases far less particulate matter than diesel.
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.