According to Central Pollution Control board (CPCB). Which particulate size in diameter (in micrometers) of the air pollutants is responsible for greatest harm to human health?

Options

A. `5.2-2.5`
B. `2.5` or less
C. `1.5` or less
D. `1.0` or less

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
- The question asks about the particulate size in diameter (in micrometers) of air pollutants that is most harmful to human health, according to the Central Pollution Control Board (CPCB).

2. **Identifying the Options:**
- The options provided are:
- A) 5.2 to 2.5 micrometers
- B) 2.5 micrometers or less
- C) 1.5 micrometers or less
- D) 1.0 micrometers or less

3. **Researching the CPCB Guidelines:**
- According to the CPCB, particulate matter (PM) is categorized based on size, and smaller particles pose a greater risk to health.

4. **Analyzing the Impact of Particulate Size:**
- Particulate matter that is 2.5 micrometers or less (PM2.5) can penetrate deep into the respiratory system, reaching the lungs and potentially entering the bloodstream.

5. **Concluding the Answer:**
- Based on the information from the CPCB, PM2.5 is responsible for significant health issues, including respiratory problems and even mortality. Therefore, the correct answer is:
- **Option B: 2.5 micrometers or less.**

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