Giddiness, reduced vision, asphyxia are caused due to

Options

A. `SO_(2)`
B. PAN
C. Acid rains
D. CO

Answer

**Step-by-Step Solution:**

1. **Understanding the Symptoms:**
- Giddiness refers to a sensation of dizziness or lightheadedness.
- Reduced vision indicates a decline in visual acuity or clarity.
- Asphyxia is a condition caused by insufficient oxygen, leading to difficulty in breathing.

2. **Identifying Possible Causes:**
- The question provides four options to identify the cause of these symptoms:
- Option A: SO2 (Sulfur Dioxide)
- Option B: PAN (Peroxyacetyl Nitrate)
- Option C: Acetones
- Option D: Carbon Monoxide

3. **Evaluating Each Option:**
- **Option A: SO2** - Sulfur dioxide is known to cause respiratory issues but is not directly linked to giddiness, reduced vision, or asphyxia. Thus, this option is incorrect.
- **Option B: PAN** - Peroxyacetyl nitrate is a secondary pollutant formed from the reaction of nitrogen oxides and volatile organic compounds. It can cause respiratory problems but is not associated with the specific symptoms mentioned. Therefore, this option is also incorrect.
- **Option C: Acetones** - Acetones are organic solvents that can cause some health effects, but they are not primarily responsible for the symptoms of giddiness, reduced vision, or asphyxia. This option is incorrect as well.
- **Option D: Carbon Monoxide (CO)** - Carbon monoxide is a colorless, odorless gas that binds with hemoglobin in the blood more effectively than oxygen does. This binding forms carboxyhemoglobin, which reduces the blood's ability to carry oxygen, leading to symptoms such as giddiness, reduced vision, and asphyxia. This option is correct.

4. **Conclusion:**
- The cause of giddiness, reduced vision, and asphyxia is due to **Carbon Monoxide (CO)** exposure.

**Final Answer: Carbon Monoxide (CO)**

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