Selected MCQ

Current Question
Which gas is essential for photosynthesis?
  • A. O₂
  • B. CO₂
  • C. N₂
  • D. H₂
Correct Answer: B
Explanation:
CO₂ is carbon source.
Related Question 1
Which gas is essential for combustion?
  • A. CO₂
  • B. O₂
  • C. N₂
  • D. H₂
Correct Answer: B
Explanation:
Oxygen supports burning.
Related Question 2
Which gas is used in photosynthesis?
  • A. O₂
  • B. CO₂
  • C. N₂
  • D. H₂
Correct Answer: B
Explanation:
CO₂ is fixed into glucose.