Which one is a `C_(4)` plant ?

Options

A. Potato
B. Mustard
C. Onion
D. Wheat.

Answer

To determine which one is a C4 plant among the given options (potato, mustard, onion, or wheat), we can follow these steps:

### Step-by-Step Solution:

1. **Understand C4 Plants**: C4 plants are adapted to high temperatures and dry environments. They have a unique photosynthetic pathway that allows them to efficiently fix carbon dioxide even under conditions where C3 plants might struggle.

2. **Identify Characteristics of C4 Plants**:
- They have a lower rate of transpiration, meaning they lose less water.
- They exhibit a lower rate of photorespiration, which allows them to use energy more efficiently during photosynthesis.

3. **Analyze the Given Options**:
- **Potato**: This is a C3 plant, typically found in cooler climates.
- **Mustard**: This is also a C3 plant, commonly grown in temperate regions.
- **Onion**: This is a C4 plant, which can thrive in warmer conditions.
- **Wheat**: This is a C3 plant, generally grown in moderate climates.

4. **Conclusion**: Based on the characteristics of C4 plants and the analysis of the options, the correct answer is **onion**, as it is the only C4 plant listed among the options.

### Final Answer:
**Onion** is a C4 plant.

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