Final answer:
CAM plants close their stomata during the day and open them at night to minimize water loss while still capturing necessary CO2 for photosynthesis. This process, known as Crassulacean Acid Metabolism (CAM), is especially common in arid environment plants like cacti and succulents. option c is correct.
Step-by-step explanation:
The correct statement about CAM plants is that their stomata remain closed during the day and open during the night. This adaptation allows CAM plants to conserve water in arid environments. During the night, the stomata open to collect, fix, and store CO2 as an organic acid, which can then be used for photosynthesis during the day when the stomata are closed to prevent water loss.
Plants such as cacti and succulents like the jade plant exhibit this Crassulacean Acid Metabolism (CAM), which is a clever evolutionary adaptation to their dry habitats. The CAM photosynthetic pathway involves fixing CO2 at night into malic acid, which is stored in vacuoles until daytime, when it is used for photosynthesis with the stomata closed to conserve water.