Name the most poisonous element.

Explanation

**Step-by-Step Solution:**

1. **Understanding Poisonous Elements**: Begin by recognizing that some elements can be classified as poisonous based on their chemical properties and the effects they have on living organisms.

2. **Identifying Plutonium**: In the periodic table, plutonium is known for its high toxicity. Its chemical symbol is Pu.

3. **Comparing with Other Elements**: When comparing plutonium with other radioactive elements, such as uranium, it is important to note that plutonium is considered more poisonous.

4. **Radiation Types**: Understand the types of radiation emitted by these elements. Uranium primarily emits beta and gamma rays, which are less harmful compared to the alpha rays emitted by plutonium.

5. **Effects on the Body**: If plutonium enters the body, it can lead to severe health issues, including the production of cancer cells. This is due to its ability to damage chromosomes within cells.

6. **Survival Rate**: The presence of plutonium in the body significantly reduces the chances of survival, often leading to a prognosis of only 5 to 10 days for affected individuals.

7. **Conclusion**: Based on the above points, the most poisonous element is identified as plutonium (Pu).

**Final Answer**: The most poisonous element is plutonium (Pu).

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