Which of the following are types of disease causing agents?

Options

A. Viruses, bacteria and fungi
B. Measles, mumps and chicken pox
C. Cholesterol, saturated fat and helminthes
D. All of these

Explanation

### Step-by-Step Solution

1. **Understanding Disease-Causing Agents**: The first step is to identify what is meant by disease-causing agents. These agents are known as pathogens, which include various microorganisms that can lead to diseases.

2. **Identifying the Options**: The question provides several options:
- Viruses, bacteria, and fungi
- Measles, mumps, and chicken pox
- Cholesterol and saturated fat
- Helminths
- All of these

3. **Analyzing Each Option**:
- **Viruses, Bacteria, and Fungi**: These are indeed types of pathogens. For example, bacteria can cause typhoid, viruses can cause polio and AIDS, and fungi can cause ringworm.
- **Measles, Mumps, and Chicken Pox**: These are diseases, not disease-causing agents. They are caused by pathogens but are not pathogens themselves.
- **Cholesterol and Saturated Fat**: These are not pathogens. They are types of substances found in food and are not responsible for causing diseases directly.
- **Helminths**: These are parasitic worms and are indeed disease-causing agents.
- **All of These**: This option suggests that all the previous options are disease-causing agents, which is incorrect since some of them are not.

4. **Conclusion**: The only correct option that lists disease-causing agents is the first one: **Viruses, Bacteria, and Fungi**. Therefore, the correct answer is the first option.

### Final Answer
The types of disease-causing agents are **Viruses, Bacteria, and Fungi**.

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