Decibel(dB) is a standard abbreviation used for the quantitative expression of

Options

A. the density of bacteria in a medium
B. a particular pollutant
C. the dominant Bacillus in a culture
D. a certain pesticide

Answer

**Step-by-Step Solution:**

1. **Understanding Decibel (dB):**
- The decibel (dB) is a unit used to measure the intensity of sound. It is a logarithmic unit that quantifies sound levels in relation to a reference level.

2. **Evaluating the Options:**
- **Option 1:** Density of bacteria in a medium - This is incorrect as density is measured in colony-forming units per milliliter (CFU/ml), not in decibels.
- **Option 2:** A particular pollutant - This option is relevant because decibels are used to measure noise pollution, which is a type of pollutant.
- **Option 3:** Dominant bacillus in a culture - This is incorrect as the measurement of bacteria is typically done in micrometers, not in decibels.
- **Option 4:** Certain pesticides - This is also incorrect since pesticides are measured in different units such as gallons or liters, not in decibels.

3. **Conclusion:**
- After evaluating all the options, the correct answer is **Option 2: A particular pollutant**, as decibels are indeed used to express the intensity of sound, which can be considered a pollutant.

**Final Answer:**
Decibel (dB) is a standard abbreviation used for the quantitative expression of a particular pollutant.

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