Which of the following elements is kept in water?

Options

A. White P
B. Na
C. S
D. Si

Answer

To determine which of the elements is kept in water, we need to analyze the properties of the elements mentioned in the context of their reactivity with water and air.

### Step-by-Step Solution:

1. **Identify the Elements**:
- The question refers to "elements" but does not specify which elements are being considered. However, based on common knowledge, we can consider elements from the nitrogen family (Group 15) such as nitrogen (N), phosphorus (P), arsenic (As), and antimony (Sb).

2. **Reactivity of Elements with Water**:
- **Nitrogen (N)**: Generally, nitrogen is inert and does not react with water.
- **Phosphorus (P)**: Specifically, white phosphorus (P4) is highly reactive and is often stored underwater to prevent it from reacting with oxygen in the air, which can lead to combustion.
- **Arsenic (As)**: Arsenic does not react with water in a significant manner and is usually stored in dry conditions.
- **Antimony (Sb)**: Antimony is also stable in water and does not react with it.

3. **Conclusion**:
- Among the elements considered, white phosphorus (P4) is the one that is specifically kept in water to prevent it from reacting with oxygen in the air. Therefore, the correct answer is white phosphorus.

### Final Answer:
- The element that is kept in water is **white phosphorus (P4)**.