Intake of `CO_2` and outlet of `O_2` is equal in photosynthesis and respiration, then the condition is known as

Options

A. Red drop
B. Solarization
C. Null point
D. Compensation point

Explanation

To solve the question regarding the condition when the intake of CO₂ and the outlet of O₂ are equal in photosynthesis and respiration, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Photosynthesis and Respiration**:
- Photosynthesis is the process by which plants convert carbon dioxide (CO₂) and water (H₂O) into glucose and oxygen (O₂) using sunlight.
- Respiration is the process where plants convert glucose and oxygen into energy, releasing carbon dioxide and water.

2. **Identifying the Condition**:
- The question states that the intake of CO₂ and the outlet of O₂ are equal. This implies that the rates of photosynthesis and respiration are balanced.

3. **Defining the Compensation Point**:
- The condition where the rate of photosynthesis equals the rate of respiration is known as the "compensation point." At this point, the amount of CO₂ absorbed during photosynthesis is equal to the amount of CO₂ released during respiration, and similarly for O₂.

4. **Conclusion**:
- Therefore, the correct answer to the question is that this condition is known as the "compensation point."

### Final Answer:
The condition is known as the **compensation point**.

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