Assertion : Total number of orbitals associated with principal quantum number n = 3 is 6.
Reason : Number of orbitals in a shell equals to 2n.

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

Explanation

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

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that the total number of orbitals associated with the principal quantum number \( n = 3 \) is 6.
- To find the total number of orbitals for a given principal quantum number \( n \), we can use the formula:
\[ \text{Total number of orbitals} = n^2 \]
- For \( n = 3 \):
\[ \text{Total number of orbitals} = 3^2 = 9 \]
- Therefore, the assertion is **false** because the total number of orbitals is 9, not 6.

2. **Understanding the Reason**:
- The reason states that the number of orbitals in a shell equals \( 2n \).
- This statement is also incorrect. The correct relationship is:
\[ \text{Number of orbitals in a shell} = n^2 \]
- For \( n = 3 \), the number of orbitals is \( 3^2 = 9 \), not \( 2n \) which would give \( 2 \times 3 = 6 \).
- Thus, the reason is also **false**.

3. **Conclusion**:
- Since both the assertion and the reason are false, the correct answer to the question is that both statements are incorrect.

### Final Answer:
Both the assertion and the reason are false.