`C_(4)` plants are abundant in

Options

A. temperate region with more humid conditions
B. temperature region with more dry conditions
C. tropical region with more humid conditions
D. tropical region with more dry conditions

Answer

### Step-by-Step Solution:

1. **Understanding C4 Plants**: C4 plants are a type of plant that have a specialized mechanism for photosynthesis, which allows them to efficiently fix carbon dioxide even in high-temperature environments. This adaptation is particularly beneficial in conditions where photorespiration (a wasteful process that occurs when oxygen levels are high and carbon dioxide levels are low) is likely to occur.

2. **Kranz Anatomy**: C4 plants exhibit a unique leaf structure known as Kranz anatomy. This structure allows for the separation of the initial carbon fixation and the Calvin cycle, which helps minimize photorespiration and increases the efficiency of photosynthesis.

3. **Environmental Conditions**: C4 plants thrive in environments characterized by high temperatures and intense sunlight. These conditions are typically found in tropical and subtropical regions.

4. **Geographical Distribution**: C4 plants are abundant in tropical regions, particularly in grasslands and savannas where the climate is warm and humid. This includes areas with high levels of sunlight and temperatures that promote rapid growth.

5. **Examples of C4 Plants**: Common examples of C4 plants include maize (corn), sorghum, and sugarcane. These plants are well-adapted to the conditions found in tropical regions.

6. **Conclusion**: Therefore, the answer to the question is that C4 plants are abundant in tropical regions, particularly in areas with high temperatures and humidity.

### Final Answer:
C4 plants are abundant in tropical regions.

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