Answer:
Option-D
Explanation:
Cellular respiration and photosynthesis are the two main physiological process which drives the life on Earth. Photosynthesis process leads to the synthesis of Glucose whereas Cellular respiration breakdown the Glucose molecule to form ATP molecules.
In plants, the photosynthesis process occurs in green leaves whereas cellular respiration occurs in every cell of the plant inside the mitochondria.
In the given question, the graph shows:
1. The absorption of oxygen till 6 am which is required during cellular respiration.
2. After 6 am, the level of oxygen production becomes more than oxygen absorption till 6 pm.
3. After 6 pm, no sunlight is available therefore photosynthesis does not occur. After this, the rate of cellular respiration increases that is oxygen is taken in.
Thus, Option-D is correct.