Which of the following is not used for disinfection of drinking water?

Options

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

Answer

To determine which of the following substances is not used for disinfection of drinking water, we need to analyze each option provided:

1. **Chlorine**:
- Chlorine is widely used in municipal water systems as a disinfectant. It is effective in killing harmful pathogens and controlling microbes in drinking water. Therefore, chlorine is used for disinfection.

2. **Ozone**:
- Ozone is another powerful disinfectant. It acts as a strong oxidizing agent and is effective in purifying water by eliminating pathogens. Thus, ozone is also used for disinfection.

3. **Chloramine**:
- Chloramine is a compound formed when ammonia is added to chlorine. It is used as a water additive to control microbes and is considered a disinfectant. Therefore, chloramine is used for disinfection.

4. **Phenyl**:
- Phenyl is a chemical that is known to be toxic and is not suitable for use in drinking water. It is primarily used as a disinfectant for surfaces and is not safe for consumption. Therefore, phenyl is not used for disinfection of drinking water.

Based on this analysis, the substance that is not used for disinfection of drinking water is **phenyl**.

### Final Answer:
**Phenyl** is not used for disinfection of drinking water.

---