Read the following text and answer the following question on the basis of the same :
all biomes of the earth constitute the earth's ecosystem. All flora and fauna occur in the lithosphere , atmosphere and hydrosphere along with the their environments . Air , water , soil , biota , temperature and light are the major environmental factors the directly affect the flora and fauna in different geological areas of the earth.
Soil aeration is inversely proportional to :

Options

A. Soil pore spaces
B. Diameter of soil particles
C. Water holding capacity of soil
D. None of the above.

Explanation

To solve the question regarding soil aeration and its inverse relationship with other factors, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Soil Aeration**: Soil aeration refers to the presence of air in the soil, which is crucial for the respiration of roots and soil organisms. Good aeration means that there are sufficient air pockets in the soil.

2. **Identify the Options**: The question provides four options to consider:
- a. Soil pore spaces
- b. Diameter of soil particles
- c. Water holding capacity of soil
- d. None of these

3. **Analyze Each Option**:
- **Option a: Soil pore spaces**: More pore spaces in the soil allow for better aeration. Thus, this option is not inversely proportional to soil aeration.
- **Option b: Diameter of soil particles**: Larger soil particles create larger spaces, allowing for better aeration. Therefore, this option is also not inversely proportional to soil aeration.
- **Option c: Water holding capacity of soil**: Soil with high water holding capacity tends to have smaller particles that fill up the spaces, reducing aeration. Hence, as water holding capacity increases, soil aeration decreases, indicating an inverse relationship.
- **Option d: None of these**: This option is not applicable since we have already identified a correct answer.

4. **Conclude the Correct Answer**: Based on the analysis, the correct answer is **c. Water holding capacity of soil**, as it is inversely proportional to soil aeration.

### Final Answer:
Soil aeration is inversely proportional to **c. Water holding capacity of soil**.

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