A primitive mammal like fossil reptile of carboniferous period was

Options

A. Dimetrodon
B. Ramapithecus
C. Rhynchocephalia
D. Steagousurs.

Answer

**Step-by-Step Solution:**

1. **Identify the Time Period**: The question refers to a primitive mammal-like fossil reptile from the Carboniferous period. The Carboniferous period is part of the Paleozoic era, known for the emergence of amphibians and early reptiles.

2. **Analyze the Options**:
- **Dimetrodon**: This is a well-known synapsid that lived during the late Carboniferous to early Permian periods. It is characterized by a distinctive sail on its back formed by elongated vertebral spines, which is a feature associated with early mammal-like reptiles.
- **Ramapithecus**: This is an early primate that lived much later than the Carboniferous period and is considered an ancestor of modern orangutans. Thus, it cannot be the answer.
- **Rhynchocephalia**: This is an order of reptiles that includes the tuatara, which also does not fit the description of a primitive mammal-like reptile from the Carboniferous.
- **Stegosaurus**: This is a dinosaur from the Jurassic period, which is far too late to be considered for the Carboniferous period.

3. **Determine the Correct Answer**: Based on the characteristics of the options, Dimetrodon fits the description of a primitive mammal-like fossil reptile from the Carboniferous period due to its vertebral column extensions and its classification as a synapsid.

4. **Conclusion**: Therefore, the correct answer to the question is **Dimetrodon**.

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