Assertion: Outermost layer of the bone is a fibrous connective tissue.
Reason: Matrix of bone is composed of protein ossein.

Options

A. If both assertion and Reason are true and the Reason is the correct explanation of the assertion.
B. If both assertion and Reason are true but the reason is not the correct explanation of the assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false.

Explanation

To solve the question, we need to analyze the assertion and the reason provided:

**Assertion:** The outermost layer of the bone is a fibrous connective tissue.
**Reason:** The matrix of bone is composed of protein ossein.

### Step-by-Step Solution:

1. **Understanding the Assertion:**
- The assertion states that the outermost layer of the bone is a fibrous connective tissue.
- The outermost layer of the bone is known as the **periosteum**, which is indeed a dense fibrous connective tissue. This layer serves as a protective covering and provides attachment for muscles and ligaments.

2. **Understanding the Reason:**
- The reason states that the matrix of bone is composed of protein ossein.
- The matrix of bone is primarily made up of collagen fibers (which can be referred to as ossein), along with mineral components like hydroxyapatite. Therefore, this statement is also true.

3. **Evaluating the Relationship:**
- Both the assertion and the reason are true statements.
- However, the reason does not directly explain the assertion. The assertion is about the outer layer of the bone (periosteum), while the reason discusses the composition of the bone matrix. Thus, the reason is not a correct explanation of the assertion.

4. **Choosing the Correct Option:**
- Based on the analysis, we find that both the assertion and the reason are true, but the reason does not provide a correct explanation for the assertion.
- Therefore, the correct option is: **Both assertion and reason are true, but reason is not the correct explanation of assertion.**

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

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