The detergents are used in comparison to soap because they-

Options

A. Provide nutrition to algae
B. Do not decomposed by bacteria
C. Make curd like white abstract with hard water
D. Are more soluble in water in comparison to soap

Explanation

### Step-by-Step Solution:

1. **Understanding Hard Water**:
- Hard water contains high levels of calcium and magnesium ions. These ions can interfere with the cleaning action of soaps.

2. **Effectiveness of Soaps in Hard Water**:
- Soaps are made from natural fats and oils. When soap is used in hard water, the calcium and magnesium ions react with the soap to form insoluble compounds (soap scum), which reduces the soap's effectiveness.

3. **Effectiveness of Detergents in Hard Water**:
- Detergents, on the other hand, are synthetic compounds that do not form insoluble compounds with calcium and magnesium ions. This means that detergents can work effectively in hard water without losing their cleaning ability.

4. **Solubility**:
- Detergents are generally more soluble in water compared to soaps. This higher solubility allows detergents to disperse more easily and clean more effectively.

5. **Cleansing Action**:
- The cleansing action of detergents is often superior to that of soaps, especially in hard water conditions. This makes detergents a preferred choice for cleaning purposes.

### Conclusion:
Detergents are used in comparison to soap because they work effectively in hard water, are more soluble in water, and have better cleansing action.

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