Note is a sound :

Options

A. of mixture of several frequencies
B. of mixture of two frequencies only
C. of a single frequencies
D. always unpleasant to listen

Explanation

**Step-by-Step Solution:**

1. **Understanding the Concept of Sound:**
- Sound is produced by vibrations that create waves in a medium (like air). These vibrations can have different frequencies.

2. **Defining a Note:**
- A note is defined as a sound that is made up of a mixture of several frequencies. This means that when we hear a note, we are actually hearing multiple sound waves at different frequencies combined together.

3. **Differentiating Between Note and Tone:**
- It is important to differentiate between a note and a tone. A tone is produced by a single frequency, while a note consists of multiple frequencies. For example, when you play a single key on a piano, you hear a tone, but when you strum a guitar, you hear a note because it combines several frequencies.

4. **Characteristics of Notes:**
- Notes can vary in pitch (related to frequency) and loudness (related to amplitude). The combination of these factors contributes to the overall sound quality of the note.

5. **Evaluating the Options:**
- The question provides several options regarding the nature of a note:
- A) Mixture of several frequencies - This is correct.
- B) Mixture of two frequencies only - This is incorrect.
- C) Of a single frequency - This is incorrect.
- D) Always unpleasant to listen - This is incorrect.
- Based on this evaluation, the correct answer is A.

**Final Answer:**
- A note is a sound that is a mixture of several frequencies.

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