Ancestors of mammals belongs to `:`

Options

A. Therapsida
B. Ornithischia
C. Silusoidea
D. Chelonia

Answer

To answer the question "Ancestors of mammals belong to:", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify the group or lineage from which mammals evolved. This involves looking into the evolutionary history of mammals.

2. **Identify the Options**: The question provides four options. We need to evaluate each option to determine which one is correct.

3. **Evaluate Each Option**:
- **Option 1: Therapsida**: This group is known as the ancestors of mammals. Therapsids are a group of synapsid reptiles that lived during the Permian and Triassic periods, and they are considered to be the direct ancestors of mammals.
- **Option 2: Ornithischia**: This group refers to a clade of dinosaurs, specifically the bird-hipped dinosaurs. They are not related to the ancestry of mammals.
- **Option 3: Shilonia**: This refers to the order of turtles. Turtles are not ancestors of mammals.
- **Option 4: None of the above**: Since we have identified Therapsida as the correct answer, this option is not applicable.

4. **Conclude the Correct Answer**: Based on the evaluation, the correct answer is **Therapsida**, as they are indeed the ancestors of mammals.

### Final Answer:
The ancestors of mammals belong to **Therapsida**.

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