Above which decibel sound becomes very harmful to the human ears?

Options

A. 30 dB
B. 60 dB
C. 70 dB
D. 120 dB

Answer

To determine the level of sound in decibels (dB) that becomes harmful to human ears, we can analyze the given options and the information provided in the video transcript.

### Step-by-Step Solution:

1. **Understanding Decibel Levels**:
- Decibels are a unit of measurement for sound intensity. The higher the decibel level, the louder the sound.

2. **Identifying Harmful Levels**:
- According to the information provided, sounds above 70 decibels can start to cause damage to our ears over time.
- Sounds above 120 decibels are considered extremely loud and can cause immediate harm to our hearing.

3. **Evaluating the Options**:
- The options given are:
- A. 30 decibels
- B. 60 decibels
- C. 70 decibels
- D. 120 decibels
- From our understanding, 30 dB and 60 dB are not harmful.
- 70 dB is the threshold where damage can begin with prolonged exposure.
- 120 dB is the level where immediate harm can occur.

4. **Conclusion**:
- Therefore, the correct answer to the question "Above which decibel sound becomes very harmful to the human ears?" is **120 decibels**.

### Final Answer:
- **120 decibels** is the level above which sound becomes very harmful to human ears.