Carbon monoxide is pollutant as it:

Options

A. it reacts with `O_(2)`
B. it inhibits glycosis
C. it reacts with haemoglobin
D. it makes nervous system inactive

Explanation

### Step-by-Step Solution:

1. **Understanding Carbon Monoxide (CO)**:
- Carbon monoxide is a colorless, odorless gas that is produced from incomplete combustion of carbon-containing fuels.

2. **Mechanism of Action**:
- Once inhaled, carbon monoxide enters the bloodstream and interacts with hemoglobin, which is the protein in red blood cells responsible for transporting oxygen.

3. **Formation of Carboxyhemoglobin**:
- Carbon monoxide binds with hemoglobin to form a compound called carboxyhemoglobin. This binding is much stronger than the binding of oxygen to hemoglobin.

4. **Impact on Oxygen Transport**:
- The formation of carboxyhemoglobin inhibits the ability of hemoglobin to carry oxygen. This results in a decreased oxygen-carrying capacity of the blood.

5. **Consequences of Carbon Monoxide Exposure**:
- The reduction in oxygen transport can lead to a condition known as carbon monoxide poisoning. Symptoms can range from mild headaches to severe health issues, including death, depending on the concentration of carbon monoxide inhaled.

6. **Identifying the Correct Option**:
- Given the options provided, the correct answer is that carbon monoxide acts as a pollutant because it reacts with hemoglobin (Option 3). The other options do not accurately describe the action of carbon monoxide.

### Final Answer:
Carbon monoxide is a pollutant as it reacts with hemoglobin, forming carboxyhemoglobin, which decreases the oxygen-carrying capacity of the blood.

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