The ancestors of Dinosaurs were

Options

A. Thecodants
B. Synapsids
C. Therapsids
D. Pelycosaurs

Answer

To determine the ancestors of dinosaurs, we need to analyze the options provided and understand the evolutionary lineage of dinosaurs.

1. **Understanding the Options:**
- Option A: Thecodons
- Option B: Synapses
- Option C: Therapsids
- Option D: Pelycosaurs

2. **Identifying the Correct Group:**
- Dinosaurs are classified as reptiles. To find their ancestors, we need to look for a group of reptiles that existed before dinosaurs.
- Thecodons refer to a group of reptiles characterized by having socketed teeth. This group is significant in the evolutionary history leading to dinosaurs.

3. **Examining Other Options:**
- Synapses: This term generally refers to connections between neurons and is not related to reptilian ancestry.
- Therapsids: These are a group of synapsids that are more closely related to mammals than to reptiles, so they are not direct ancestors of dinosaurs.
- Pelycosaurs: These are early synapsids and are also not directly related to the lineage of dinosaurs.

4. **Conclusion:**
- Based on the analysis, the ancestors of dinosaurs are best represented by the group known as thecodons. This group falls under the category of Triassic reptiles, which are the direct ancestors of dinosaurs.

**Final Answer: The ancestors of dinosaurs were thecodons.**

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