Which of the following is responsible for causing "Toxoplasmosis' as an opportunistic infection in individuals suffering from AIDS?

Options

A. Bacteria
B. Virus
C. Fungi
D. Protozoa

Answer

To solve the question regarding which organism is responsible for causing "Toxoplasmosis" as an opportunistic infection in individuals suffering from AIDS, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the causative agent of Toxoplasmosis, particularly in the context of AIDS patients. Toxoplasmosis is known to be an opportunistic infection that can affect individuals with weakened immune systems, such as those with AIDS.

2. **Identify the Options**: The options provided are:
- Option 1: Bacteria
- Option 2: Virus
- Option 3: Fungi
- Option 4: Protozoa

3. **Evaluate Each Option**:
- **Option 1: Bacteria**: Toxoplasmosis is not caused by bacteria. Therefore, this option is incorrect.
- **Option 2: Virus**: The virus associated with AIDS is the Human Immunodeficiency Virus (HIV), but Toxoplasmosis is not caused by a virus. Thus, this option is also incorrect.
- **Option 3: Fungi**: Toxoplasmosis is not caused by fungi. This option is incorrect as well.
- **Option 4: Protozoa**: Toxoplasmosis is caused by the protozoan parasite Toxoplasma gondii. This option is correct.

4. **Conclusion**: After evaluating all the options, the correct answer is Option 4: Protozoa, as Toxoplasma gondii is a protozoan parasite responsible for causing Toxoplasmosis.

### Final Answer:
The organism responsible for causing Toxoplasmosis as an opportunistic infection in individuals suffering from AIDS is **Protozoa** (specifically, Toxoplasma gondii).

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