Which disinfectant cannot be used in drinking water?

Options

A. Chlorine
B. Ozone
C. Chloramine
D. Phenyl

Answer

To solve the question "Which disinfectant cannot be used in drinking water?", we will analyze the options provided: chlorine, ozone, chloramine, and phenyl.

### Step-by-Step Solution:

1. **Understanding Disinfectants**: Disinfectants are substances that are added to water to kill microorganisms and improve water quality. Common disinfectants include chlorine, ozone, and chloramine.

2. **Evaluating the Options**:
- **Chlorine**: This is a widely used disinfectant in water treatment. It effectively kills bacteria and viruses, making it safe for drinking water.
- **Ozone**: Another effective disinfectant, ozone is used in water treatment processes. It is known for its strong oxidizing properties and does not leave harmful residues.
- **Chloramine**: This is a compound formed from chlorine and ammonia. It is also used as a disinfectant in drinking water treatment and is generally considered safe.
- **Phenyl**: While phenyl is a disinfectant, it is also toxic and has a strong, unpleasant odor. It is not suitable for use in drinking water due to its harmful effects.

3. **Conclusion**: Among the given options, phenyl is the disinfectant that cannot be used in drinking water because it is poisonous and makes the water unfit for consumption.

### Final Answer:
The disinfectant that cannot be used in drinking water is **phenyl**.

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