Assertion : Male has deeper pitch of sound than female .
Reason : At puberty , size of larynx and vocal cords increase in male .

Options

A. If both Assertion and Reason are true and Reason is a correct explaintion of Assertion .
B. If both assertion and Reason are true but Reason is not a correct explanation of Assertion .
C. If Assertion is true but Reason is false .
D. If both assertion and Reason are false .

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Male has a deeper pitch of sound than female." This is a true statement. Males generally have a deeper voice compared to females.

2. **Understanding the Reason**:
- The reason provided is "At puberty, size of larynx and vocal cords increase in males." This statement is also true. During puberty, males experience an increase in the size of their larynx (voice box) and vocal cords due to hormonal changes, particularly the increase in testosterone.

3. **Connecting Assertion and Reason**:
- The reason explains why the assertion is true. The increase in the size of the larynx and vocal cords in males leads to a deeper pitch of sound. Therefore, the reason is a correct explanation of the assertion.

4. **Evaluating the Options**:
- Based on the analysis:
- Both the assertion and reason are true.
- The reason is the correct explanation for the assertion.
- Thus, the correct option is: "Both assertion and reason are true. Reason is the correct explanation of assertion."

### Final Answer:
The correct answer is: **Both assertion and reason are true. Reason is the correct explanation of assertion.**

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