In the nighttime, it is advised not to sleep under trees because
- Athey liberate less amount of oxygen
- Bthey liberate harmful gases at night
- Cthey liberate carbon dioxide
- Dthey liberate carbon monoxide
- ENone of the above/More than one of the above
Show answer and explanation
Correct answer: (c) they liberate carbon dioxide
Explanation
At night there is no light, so plants stop photosynthesis but continue respiration.
During respiration they take in oxygen and release carbon dioxide (CO2), lowering oxygen around the sleeper.
By day, photosynthesis dominates and they release oxygen, so the warning applies only at night.