A free living round worm occurring in very large number is soil is

Options

A. Rhabditis
B. Millipede
C. Earthworm
D. Fasciola

Answer

To solve the question "A free living round worm occurring in very large numbers in soil is," we will analyze the options provided and determine which one correctly identifies the organism in question.

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify a free-living roundworm that is commonly found in soil.

2. **Evaluate the Options**:
- **Option A: Reptiles**: This is not a type of roundworm; reptiles are a class of animals that include snakes, lizards, and turtles.
- **Option B: Melipidae**: This refers to a family of bees, not roundworms.
- **Option C: Earthworm**: Earthworms are segmented worms (Annelida), not roundworms (Nematoda).
- **Option D: Fasciola**: This is a genus of parasitic flatworms known as liver flukes, which do not live freely in the soil.

3. **Identify the Correct Answer**: None of the options provided directly mention a free-living roundworm. However, based on common knowledge, the term "roundworm" typically refers to nematodes, which are abundant in soil. The most appropriate answer, if it were an option, would be a type of nematode (like Caenorhabditis elegans), but since none of the options fit this description, we conclude that the question may have an error.

4. **Conclusion**: Since the options do not include a correct answer, it is important to clarify that free-living roundworms in soil are generally nematodes, and none of the provided options are correct.

### Final Answer: None of the provided options (Reptiles, Melipidae, Earthworm, Fasciola) correctly identify a free-living roundworm in soil.

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