Which elements provide rigidity to teeth & bones?

Options

A. Iron & Calcium
B. Calcium and Magnesium
C. Phosphorous and Sodium
D. Iron and phosphorous

Answer

To determine which elements provide rigidity to teeth and bones, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Components of Teeth and Bones**:
- Teeth and bones are composed of various elements, including calcium, phosphorus, magnesium, and others.

2. **Understand the Role of Each Element**:
- Calcium is a crucial element that contributes significantly to the rigidity and strength of bones and teeth.
- Magnesium also plays a role in maintaining the structural integrity of bones.

3. **Evaluate the Options Provided**:
- **Option A**: Iron and Calcium - While calcium is correct, iron does not primarily provide rigidity to bones and teeth.
- **Option B**: Calcium and Magnesium - Both of these elements are known to contribute to the rigidity of bones and teeth.
- **Option C**: Phosphorus and Sodium - While phosphorus is present, it does not primarily provide rigidity; sodium is not a major component in this context.
- **Option D**: Iron and Phosphorus - Neither of these elements primarily contributes to rigidity in bones and teeth.

4. **Conclusion**:
- The correct answer is **Option B: Calcium and Magnesium**, as both elements are essential for providing rigidity to teeth and bones.

### Final Answer:
The elements that provide rigidity to teeth and bones are **Calcium and Magnesium**.

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