In can regenerate entire alimentary canal

Options

A. Fish
B. Bird
C. Amphibians
D. Sea cucumber

Answer

To solve the question regarding which organism can regenerate its entire alimentary canal, we will analyze the options provided and the process of regeneration in different animals.

### Step-by-Step Solution:

1. **Understanding Regeneration**:
- Regeneration is the biological process where organisms can renew, restore, or grow back lost or damaged tissues or organs. This ability varies among different species.

2. **Analyzing the Options**:
- **Option A: Fish**: Fish are known for their ability to regenerate fins, but they do not regenerate their entire alimentary canal.
- **Option B: Bird**: Birds can regenerate feathers and some cells, but they do not have the capability to regenerate their alimentary canal.
- **Option C: Amphibians**: Amphibians, like salamanders, can regenerate limbs and tails, but they do not regenerate their entire alimentary canal.
- **Option D: Sea Cucumber**: Sea cucumbers have a unique ability to regenerate their entire alimentary canal. They can expel their digestive system as a defense mechanism and later regenerate it.

3. **Conclusion**:
- Based on the analysis, the organism that can regenerate its entire alimentary canal is **Option D: Sea Cucumber**.

### Final Answer:
**The correct answer is Option D: Sea Cucumber.**

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