Drinking water must be

Options

A. hard
B. soft or hard
C. soft
D. none of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding Water Hardness:**
- Drinking water can be classified as hard or soft. Hard water contains high levels of minerals, particularly calcium and magnesium, while soft water has lower concentrations of these minerals.

2. **Identifying Hard Water:**
- Hard water can be identified by certain characteristics such as:
- Formation of soap scum or a film when washing hands.
- Mineral stains on glasses or dishes after washing.
- Reduced water pressure in plumbing systems.

3. **Effects of Hard Water:**
- While hard water is not typically harmful to health, it can have adverse effects on skin and hair, such as:
- Dry skin.
- Dry and itchy hair.
- Altered pH balance of the skin.

4. **Benefits of Soft Water:**
- Soft water is generally considered better for drinking because:
- It can contain higher levels of beneficial minerals like potassium and sodium.
- It helps in better retention of minerals in the body.

5. **Conclusion:**
- Based on the analysis, drinking water should ideally be soft rather than hard. Therefore, the correct answer is that drinking water must be soft.

**Final Answer:**
Drinking water must be soft.

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