It can regenerate entire alimentary canal

Options

A. Amphibian
B. Fish
C. Sea cucumber
D. Parthenogenesis

Answer

To solve the question "It can regenerate entire alimentary canal," we need to analyze the options provided: amphibian, fish, sea cucumber, and parthenogenesis.

### Step-by-Step Solution:

1. **Understanding the Question**: We need to identify which organism has the ability to regenerate its entire alimentary canal.

2. **Analyzing Option A: Amphibians**:
- Amphibians, such as frogs and salamanders, can regenerate certain body parts, but they do not regenerate their entire alimentary canal. They can regenerate limbs and tails but not the complete digestive system.

3. **Analyzing Option B: Fish**:
- Fish are known for their regenerative abilities, particularly with their fins. However, they do not have the capability to regenerate their entire alimentary canal.

4. **Analyzing Option C: Sea Cucumber**:
- Sea cucumbers have a unique ability to discard their alimentary canal as a defense mechanism. They can regenerate their entire digestive system after expelling it. This makes sea cucumber a strong candidate for the answer.

5. **Analyzing Option D: Parthenogenesis**:
- Parthenogenesis is a form of asexual reproduction where an organism can develop from an unfertilized egg. It does not relate to regeneration of body parts or systems.

6. **Conclusion**: Based on the analysis, the organism that can regenerate its entire alimentary canal is the sea cucumber. Therefore, the correct answer is option C.

### Final Answer:
**C. Sea Cucumber**