Which of the following sexually transmitted diseases is caused by a protozoan?

Options

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

Answer

To determine which sexually transmitted disease (STD) is caused by a protozoan, we can analyze the options provided:

1. **Gonorrhea**: This disease is caused by a bacterium known as *Neisseria gonorrhoeae*. Therefore, it is not caused by a protozoan.

2. **Trichomoniasis**: This disease is caused by a protozoan called *Trichomonas vaginalis*. This indicates that trichomoniasis is indeed caused by a protozoan.

3. **Chlamydiasis**: This disease is caused by a bacterium known as *Chlamydia trachomatis*. Thus, it is not caused by a protozoan.

4. **Syphilis**: This disease is caused by a bacterium named *Treponema pallidum*. Therefore, it is also not caused by a protozoan.

After analyzing all the options, we find that the only sexually transmitted disease caused by a protozoan is **trichomoniasis**.

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

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