Edaphic factor refers to

Options

A. water
B. soil
C. relative humidity
D. altitude

Explanation

**Step-by-Step Solution:**

1. **Understanding Edaphic Factors**: Edaphic factors are primarily related to the soil and its characteristics. This includes various aspects that influence the soil's ability to support life.

2. **Soil Texture**: One of the key components of edaphic factors is soil texture. This refers to the size of the soil particles and how they are arranged, which can affect water retention and nutrient availability.

3. **Soil Composition**: Edaphic factors also encompass the mineral composition of the soil. Different minerals contribute to the fertility of the soil and its ability to support different types of vegetation.

4. **Soil Topography**: The physical features of the land, or soil topography, are also considered edaphic factors. This includes the slope, elevation, and landscape position, which can influence drainage and erosion.

5. **Soil pH**: The pH level of the soil is another important edaphic factor. It affects nutrient availability and the types of organisms that can thrive in that soil.

6. **Water and Humidity**: While water and relative humidity are important for ecosystems, they are generally classified as climatic factors rather than edaphic factors. Edaphic factors focus specifically on soil-related characteristics.

7. **Conclusion**: In summary, edaphic factors refer to the characteristics of the soil, including its texture, composition, topography, and pH, which all play a crucial role in determining the types of ecosystems that can exist in a given area.

**Final Answer**: Edaphic factors refer to the soil and its characteristics, including soil texture, composition, topography, and pH.

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