A : The pitch of female voice is higher than the pitch of male voice .
R : Pitch distinguishes between a shrill and a grave sound .

Answer

To analyze the statements given in the question, we will break down the assertion and the reason step by step.

### Step 1: Understand the Assertion
**Assertion (A)**: The pitch of the female voice is higher than the pitch of the male voice.

- This statement is true. Generally, female voices are characterized by a higher pitch compared to male voices. This difference in pitch is primarily due to the physical structure of the vocal cords.

**Hint**: Consider how the anatomy of vocal cords affects sound production.

### Step 2: Understand the Reason
**Reason (R)**: Pitch distinguishes between a shrill and a grave sound.

- This statement is also true. Pitch is a perceptual property of sounds that allows us to categorize them as high (shrill) or low (grave). For example, a high-pitched sound like a whistle is considered shrill, while a low-pitched sound like a drum is considered grave.

**Hint**: Think about examples of sounds that illustrate high and low pitch.

### Step 3: Analyze the Relationship Between A and R
- While both statements are true, we need to determine if the reason (R) correctly explains the assertion (A).
- The assertion is about the difference in pitch between male and female voices, while the reason discusses the general concept of pitch distinguishing between types of sounds.

**Hint**: Reflect on whether the reason directly supports the assertion.

### Step 4: Conclusion
- Both the assertion and the reason are correct, but the reason does not provide a direct explanation for the assertion. Therefore, while they are related concepts, the reason does not clarify why female voices have a higher pitch than male voices.

**Final Answer**: Both A and R are correct, but R is not the correct explanation for A.

### Summary of the Steps:
1. Identify the truth of the assertion regarding pitch differences.
2. Recognize the truth of the reason about pitch distinguishing sound types.
3. Evaluate the relationship between A and R to conclude their correctness and explanatory power.