Ornithorhyncus is a

Options

A. Duck
B. Dinosaur
C. Monotreme mammal
D. A fossil bird .

Answer

**Step-by-Step Solution:**

1. **Identify the Subject**: The question asks about "Ornithorhynchus". Recognize that this term refers to a specific animal.

2. **Common Name**: Understand that "Ornithorhynchus" is commonly known as the "duck-billed platypus".

3. **Classification**: Determine the classification of the duck-billed platypus. It is a type of mammal.

4. **Reproductive Method**: Note that the duck-billed platypus is unique among mammals because it lays eggs, which is a characteristic of a specific group of mammals.

5. **Group Identification**: Identify that the group of mammals that lay eggs is known as "monotremes".

6. **Geographical Distribution**: Recognize that the duck-billed platypus is endemic to eastern Australia, meaning it is native to that region.

7. **Conclusion**: Based on the classification and characteristics, conclude that "Ornithorhynchus" is a monotreme mammal.

**Final Answer**: Ornithorhynchus is a monotreme mammal.

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