Name three major greenhouse gases and explain their role in climate change.

• A. Ozone, sulfur hexafluoride, and neon trap infrared radiation.
• B. Oxygen, nitrogen, argon are major greenhouse gases.
• C. Carbon dioxide, methane, and nitrous oxide trap infrared radiation, increasing the atmosphere's heat.
• D. Water vapor is the only greenhouse gas.

Answer: (C)

Greenhouse gases are molecules that absorb infrared radiation from the Earth and re-emit it back toward the surface, trapping heat and warming the planet. The trio carbon dioxide, methane, and nitrous oxide are considered major contributors because they occur in the atmosphere in significant amounts, have strong infrared absorption, and persist for long periods, so they exert substantial warming over time. Human activities—burning fossil fuels, agriculture, and industry—increase these gases, boosting the planet’s average temperature.

Water vapor also traps heat, but its amount in the atmosphere is largely controlled by temperature itself, so it acts more as a feedback to warming rather than a primary driver. The other options either include gases that don’t significantly absorb infrared (like neon and inert major atmospheric gases) or make an incorrect claim about the uniqueness of greenhouse gases.