Plant Physiology

Step 1: Understand the stomatal function in plants.
In most plants, stomata are open during the day for photosynthesis and closed at night.
However, in CAM (Crassulacean Acid Metabolism) plants, the stomata are opened at night to reduce water loss and allow for carbon dioxide to be absorbed.
Step 2: Identify the plant types.
C3 and C4 plants typically open their stomata during the day. CAM plants open their stomata at night to minimize water loss. Hydrolytic plants do not have this characteristic.
Conclusion: The correct answer is (C) CAM plants.