Which of the following is the most dangerous metal pollutant of automobile exhaust ?

Options

A. Cadmium
B. Copper
C. Mercury
D. Lead

Explanation

To determine the most dangerous metal pollutant of automobile exhaust from the given options (cadmium, copper, mercury, and lead), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Automobile Exhaust**:
- Automobile exhaust is a byproduct of burning fuel in vehicles. It contains various pollutants, including metals.

2. **Identifying the Options**:
- The options provided are cadmium, copper, mercury, and lead. We need to evaluate these metals based on their presence and toxicity in automobile exhaust.

3. **Analyzing Each Metal**:
- **Cadmium**: While it is toxic, it is not a primary pollutant from automobile exhaust.
- **Copper**: This metal can be found in brake linings and other components but is not considered the most dangerous pollutant from exhaust.
- **Mercury**: This is a toxic metal, but its presence in automobile exhaust is not as significant as lead.
- **Lead**: Historically, lead was used in gasoline as an anti-knock agent. It is known to be highly toxic and is associated with severe health risks, including lead poisoning.

4. **Conclusion**:
- Among the options, lead is the most dangerous metal pollutant of automobile exhaust due to its high toxicity and historical use in gasoline.

### Final Answer:
- The most dangerous metal pollutant of automobile exhaust is **Lead**.

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