High concentration of Pb in human blood damages

Options

A. Kidneys
B. Liver
C. Brain
D. All of these

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the effects of high concentrations of lead (Pb) in human blood. Lead is a toxic heavy metal that can have various harmful effects on the body.

2. **Identifying Affected Organs**: The options provided are:
- Kidney
- Liver
- Brain

3. **Researching Effects of Lead Exposure**:
- **Kidneys**: High levels of lead can cause kidney damage and dysfunction. Lead can accumulate in the kidneys and impair their ability to filter waste from the blood.
- **Liver**: Lead exposure can lead to liver damage, including conditions such as cirrhosis, which can result in liver failure.
- **Brain**: Lead is particularly harmful to the nervous system. It can cause neurological damage, cognitive deficits, and behavioral issues, especially in children.

4. **Summarizing the Effects**: Based on the research:
- Lead can cause anemia and weakness.
- It can lead to kidney dysfunction and damage.
- It can cause liver damage, including cirrhosis.
- It can result in brain damage and neurological issues.

5. **Conclusion**: Since high concentrations of lead in the blood can damage the kidneys, liver, and brain, the correct answer to the question is that all of these organs can be affected.

### Final Answer:
High concentration of Pb in human blood damages the kidneys, liver, and brain. Therefore, the correct option is **all of these**.

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