A : A particle at the corner of CCP unit cell has `(1)/(8)th` of its contribution to the unit cell.
R : In any space lattice the corner of the unit cell is always shared by the eight unit cell.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion then mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

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

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that a particle at the corner of a CCP (Cubic Close Packing) unit cell contributes \( \frac{1}{8} \) of its total to the unit cell.
- In a CCP unit cell, which is also known as the Face-Centered Cubic (FCC) structure, particles are located at the corners and the face centers.

2. **Understanding the Reason**:
- The reason states that in any space lattice, the corner of the unit cell is always shared by eight unit cells.
- This means that any atom located at a corner of the unit cell is actually part of eight adjacent unit cells.

3. **Contribution Calculation**:
- Since a corner atom is shared by 8 unit cells, the contribution of one corner atom to the unit cell is calculated as:
\[ \text{Contribution} = \frac{1 \text{ atom}}{8 \text{ unit cells}} = \frac{1}{8} \]
- Therefore, each corner atom contributes \( \frac{1}{8} \) of its total to the unit cell.

4. **Conclusion**:
- Both the assertion and the reason are true. The reason correctly explains why the assertion is true.
- Thus, the final conclusion is that both statements are valid and the reason provides the correct explanation for the assertion.

### Final Answer:
Both the assertion and the reason are true, and the reason correctly explains the assertion.