Bacterial pathogen can be controlled by

Options

A. p-amino benzoic acid
B. Malonate
C. Sulphanilamide
D. All of these

Answer

To answer the question "Bacterial pathogen can be controlled by," we need to evaluate the options provided: paraminobenzoic acid, malonate, and sulfanilamide.

### Step-by-Step Solution:

1. **Understand the Options**:
- **Paraminobenzoic Acid (PABA)**: This compound is known to be a part of folic acid and is found in various foods. It is used in some treatments for skin conditions but does not have a direct role in controlling bacterial pathogens.

- **Malonate**: This is a compound that is found in certain fruits like grapes and strawberries. It is primarily used in organic synthesis and does not have a known role in controlling bacterial infections.

- **Sulfanilamide**: This is a well-known antibacterial agent that works as a bacteriostatic. It inhibits the growth of bacteria by interfering with their ability to synthesize folic acid, which is essential for their growth and reproduction.

2. **Evaluate the Effectiveness**:
- Since PABA and malonate do not directly inhibit bacterial growth or act as antibacterial agents, they are not suitable for controlling bacterial pathogens.
- Sulfanilamide, on the other hand, specifically targets bacteria and inhibits their growth, making it an effective choice for controlling bacterial pathogens.

3. **Conclusion**:
- The correct answer to the question is **sulfanilamide**, as it is the only option that effectively controls bacterial pathogens by inhibiting their growth.

### Final Answer:
Bacterial pathogens can be controlled by **sulfanilamide**.

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