X' is the skeleton which is present inside the body of an organism 'Y'.
Select the option which correctly identifies X and Y.

Options

A. `{:(X, Y), ("Bony exoskeleton", "Earthworm"):}`
B. `{:(X, Y), ("Soft exoskeleton", "Snail"):}`
C. `{:(X, Y), ("Liquid endoskeleton", "Earthworm"):}`
D. `{:(X, Y), ("Bony endoskeleton", "Snail"):}`

Explanation

To solve the question, we need to identify what X and Y are based on the description provided.

### Step-by-Step Solution:

1. **Understanding the Terms**:
- X is described as a skeleton present inside the body of an organism Y.
- Skeletons can be categorized as endoskeletons (inside the body) or exoskeletons (outside the body).

2. **Identifying X**:
- Since X is a skeleton found inside the body, it must be an endoskeleton.
- There are two main types of endoskeletons: bony endoskeletons (made of bones) and liquid endoskeletons (like those found in some invertebrates).

3. **Identifying Y**:
- We need to find an organism that has an endoskeleton.
- The question provides examples of organisms: earthworm, snail, etc.

4. **Analyzing the Organisms**:
- **Earthworm**: It does not have bones but has a liquid endoskeleton (the fluid inside its body provides support).
- **Snail**: It has a hard shell (exoskeleton) made of calcium carbonate, not an endoskeleton.

5. **Conclusion**:
- The only organism from the examples that fits the description of having an endoskeleton (specifically a liquid endoskeleton) is the earthworm.
- Therefore, we can conclude that X is a liquid endoskeleton and Y is an earthworm.

### Final Answer:
X = Liquid Endoskeleton, Y = Earthworm

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