……are CAM plant

Options

A. Maize
B. Pineapple
C. Onion
D. Pea.

Answer

To answer the question "……are CAM plants," we need to identify which of the provided options is a CAM (Crassulacean Acid Metabolism) plant. Let's analyze the options step by step.

### Step-by-Step Solution:

1. **Understanding CAM Plants**:
- CAM plants are a type of plant that photosynthesize using a special pathway known as Crassulacean Acid Metabolism (CAM). This adaptation allows them to conserve water in arid conditions.

2. **Characteristics of CAM Plants**:
- They are typically succulent, meaning they have thick, fleshy tissues that store water.
- They possess a low surface area to volume ratio, which helps minimize water loss through transpiration.

3. **Analyzing the Options**:
- **Maize**: This is a C4 plant, not a CAM plant. C4 plants have a different photosynthetic pathway.
- **Pineapple**: This is known to be a CAM plant. It has adaptations for water conservation and utilizes the CAM pathway for photosynthesis.
- **Onion**: This is a bulbous plant and does not fall under the category of CAM plants.
- **Pea**: This is a legume and also does not utilize the CAM pathway.

4. **Conclusion**:
- Among the given options, the only plant that is classified as a CAM plant is **pineapple**.

### Final Answer:
Pineapple are CAM plants.

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