Which of the following sexually transmitted diseases is caused y a protozon ?

Options

A. Gonorrhoea
B. Trichomoniasis
C. Chlamydiasis
D. Syphilis

Answer

To determine which sexually transmitted disease (STD) is caused by a protozoan, we will analyze the given options one by one.

### Step-by-Step Solution:

1. **Identify the Options**: The question provides several options for sexually transmitted diseases. We need to evaluate each one to find out which is caused by a protozoan.

2. **Evaluate Gonorrhea**:
- Gonorrhea is known to be caused by the bacterium *Neisseria gonorrhoeae*.
- Therefore, this option is not caused by a protozoan.

3. **Evaluate Trichomoniasis**:
- Trichomoniasis is caused by the protozoan *Trichomonas vaginalis*.
- This option is indeed caused by a protozoan.

4. **Evaluate Chlamydia**:
- Chlamydia is caused by the bacterium *Chlamydia trachomatis*.
- So, this option is also not caused by a protozoan.

5. **Evaluate Syphilis**:
- Syphilis is caused by the bacterium *Treponema pallidum*.
- Therefore, this option is also not caused by a protozoan.

6. **Conclusion**: After evaluating all the options, the only sexually transmitted disease caused by a protozoan is **Trichomoniasis**.

### Final Answer:
The sexually transmitted disease caused by a protozoan is **B. Trichomoniasis**.

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