Which one of these substances should ideally NOT be present in potable water?

Options

A. Carbon dioxide
B. Mineral salts
C. Oxygen
D. SPMs

Explanation

**Step-by-Step Solution:**

1. **Understanding Potable Water**: Potable water is water that is safe for human consumption. It should meet certain criteria to be considered safe to drink.

2. **Criteria for Potable Water**:
- **Tasteless**: Potable water should not have any taste.
- **Colorless**: It should be clear and transparent, without any color.
- **Odorless**: There should be no smell or odor in the water.
- **Free from Impurities**: Potable water should not contain any pollutants or contaminants.

3. **Analyzing the Substances**:
- **Carbon Dioxide (a)**: This gas is naturally present in both air and water and does not pose a health risk in small amounts.
- **Mineral Salts (b)**: These are essential for health and are often present in potable water.
- **Oxygen (c)**: Oxygen is also soluble in water and is necessary for aquatic life; it is safe for human consumption.
- **Suspended Particulate Matter (SPM) (d)**: SPM refers to tiny particles that can contaminate water. These particles can cause respiratory and cardiovascular diseases if ingested.

4. **Conclusion**: Among the given options, Suspended Particulate Matter (SPM) is the substance that should ideally NOT be present in potable water, as it is a pollutant and poses health risks.

**Final Answer**: d. SPM (Suspended Particulate Matter)

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