Assertion :- Endoskeleton of sturthio is fully ossified.
Reason :- It is flightless birds.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are false.

Answer

To solve the question regarding the assertion and reason about the endoskeleton of the ostrich (Sturthio), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Assertion**:
- The assertion states that "the endoskeleton of Sturthio is fully ossified."
- This means that the bones of the ostrich are completely developed and hardened.

2. **Evaluate the Assertion**:
- The assertion is indeed correct. Ostriches, being birds, have an endoskeleton that is fully ossified. This is typical for birds as it provides structural support and is necessary for their body functions.

3. **Understand the Reason**:
- The reason states that "it is a flightless bird."
- This indicates that the ostrich does not have the ability to fly.

4. **Evaluate the Reason**:
- The reason is also correct. Ostriches are known as flightless birds and are the largest living birds. They are adapted to running rather than flying.

5. **Determine the Relationship**:
- Now, we need to analyze the relationship between the assertion and the reason. While both statements are true, the reason does not explain why the endoskeleton is fully ossified. The ossification of bones is not directly related to the bird's ability or inability to fly.

6. **Choose the Correct Answer**:
- Based on the evaluations, the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion. Therefore, the answer is option 2.

### Final Answer:
Both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

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