Which of the following metals causes harmful effects?

Options

A. Lead
B. Cobalt
C. Uranium
D. All of the above

Answer

**Step-by-Step Solution:**

1. **Identify the Metals in Question**: The metals listed are lead, cobalt, uranium, and an option for all of the above.

2. **Evaluate the First Metal - Lead**:
- Lead is known to be released from vehicular emissions.
- It persists in the environment and accumulates in living organisms.
- Lead exposure can lead to severe neurological degradation, particularly affecting cognitive functions and development in children.

3. **Evaluate the Second Metal - Cobalt**:
- Cobalt is associated with health issues such as cardiomyopathy, where the heart becomes enlarged and inefficient.
- Other effects of cobalt exposure include nausea, headaches, and lung disorders, indicating its harmful effects on health.

4. **Evaluate the Third Metal - Uranium**:
- Uranium is a radioactive element that emits highly ionizing radiation.
- Exposure to uranium can lead to serious health issues, including bone and liver cancer, due to its radioactive properties.

5. **Conclusion**: Since all three metals (lead, cobalt, and uranium) have been shown to cause harmful effects on human health and the environment, the correct answer is "all of the above."

**Final Answer**: All of the above.

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