issb general knowledge MCQ #11

Largest proportion of Earth's atmosphere by volume?

issb general knowledge MCQ #11

  1. Question 1

    Q1. Largest proportion of Earth's atmosphere by volume?

    • A) Oxygen
    • B) Carbon dioxide
    • C) Nitrogen
    • D) Argon

    Answer: Nitrogen

    Explanation: Nitrogen ~78%, oxygen ~21%. CO₂ is a trace gas. This fact often appears in ISSB academic and general knowledge sections.