issb general knowledge MCQ #519

Which gas do humans need to breathe?

issb general knowledge MCQ #519

  1. Question 1

    Q1. Which gas do humans need to breathe?

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

    Answer: Oxygen

    Explanation: Humans require oxygen for cellular respiration. Oxygen is correct because it matches what the question requires. Remember this fact for ISSB general knowledge sections.