For transmission of speeches, talks, music, dramas etc. is used

Options

A. radio broadcast transmitter
B. radio telegraph transmitter
C. navigation transmitter
D. None of these

Explanation

To solve the question regarding the transmission of speeches, talks, music, dramas, etc., we need to analyze the options provided and understand the functions of each.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the medium or method used for the transmission of various audio forms like speeches, talks, music, and dramas.

2. **Analyzing the Options**:
- **Radio Broadcast**: This is a method of transmitting audio content over radio waves. It is commonly used for speeches, music, and other forms of audio entertainment.
- **Transmitter**: This is a device that sends out signals, but it does not specify the type of content transmitted.
- **Radio**: This refers to the device that receives radio signals but does not indicate the transmission method.
- **Telegraph**: This is used for sending coded messages, not suitable for audio transmission.
- **Navigation Transmitter**: This is used for navigation purposes and does not transmit audio content.
- **None of these**: This option suggests that none of the previous options are correct.

3. **Identifying the Best Option**:
- Since the question specifically mentions the transmission of audio content, the most suitable option is **Radio Broadcast**. Radio broadcasts are designed to transmit various audio forms, including speeches, music, and dramas.

4. **Conclusion**: Based on the analysis, the correct answer to the question is **Radio Broadcast**.

### Final Answer:
**Radio Broadcast**

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