An incubatorium is found in the female of

Options

A. Echidna
B. Platypus
C. Water Shrew
D. Tree Shrew.

Answer

**Step-by-Step Solution:**

1. **Understand the Term "Incubatorium":**
- An incubatorium is defined as a ventral brooding pouch. It is a specialized structure that aids in the incubation of eggs or young offspring.

2. **Identify the Organisms Listed in the Options:**
- The options provided are:
- Option 1: Echidna
- Option 2: Platypus
- Option 3: Water shrew
- Option 4: Tree shrew

3. **Analyze Each Option:**
- **Echidna:** This is a monotreme, a type of egg-laying mammal, and females have a pouch (incubatorium) for brooding their eggs.
- **Platypus:** Another monotreme, but it does not have a distinct incubatorium; it lays eggs and incubates them in a burrow.
- **Water Shrew:** This is a eutherian mammal and does not have an incubatorium.
- **Tree Shrew:** Also a eutherian mammal, lacking an incubatorium.

4. **Determine the Correct Answer:**
- Based on the analysis, the only organism that possesses an incubatorium is the **Echidna**.

5. **Conclusion:**
- Therefore, the correct answer to the question is that an incubatorium is found in the female of the **Echidna**.

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