Humus is

Options

A. Completely deomposed organic matter
B. Partially decomposed organic matter
C. partially decomposed inorganic matter
D. Completely decomposed inorganic matter

Explanation

**Step-by-Step Solution:**

1. **Understanding Humus**: Humus is a component of soil that consists of organic matter. It is formed from the decomposition of plant and animal materials.

2. **Decomposition Process**: The process of creating humus involves the breakdown of organic materials such as leaves, grass, and other plant remains. This breakdown is carried out by microorganisms and other decomposers.

3. **Identifying the Type of Decomposition**: Humus is not completely decomposed; rather, it is partially decomposed organic matter. This means that while it has undergone some breakdown, it still retains some of the original structure and nutrients of the organic material.

4. **Evaluating the Options**:
- Option 1: Completely decomposed organic matter - Incorrect, as humus is not fully decomposed.
- Option 2: Partially decomposed organic matter - Correct, as this accurately describes humus.
- Option 3: Partially decomposed inorganic matter - Incorrect, as humus is organic, not inorganic.
- Option 4: Completely decomposed inorganic matter - Incorrect, as humus is organic and not completely decomposed.

5. **Conclusion**: Based on the definitions and characteristics of humus, the correct answer is Option 2: "Partially decomposed organic matter."