The chemotherapeutic substance derived from living organismas that has an inhibitory effect on parasitic organisms is known as

Options

A. Option1 Exotoxin
B. Option2 Bactericide
C. Option3 Antibody
D. Option4 Antibiotic

Answer

To solve the question, "The chemotherapeutic substance derived from living organisms that has an inhibitory effect on parasitic organisms is known as," we can follow these steps:

### Step 1: Understand the Question
We need to identify a substance that is derived from living organisms and has an inhibitory effect on parasitic organisms.

### Step 2: Identify Key Terms
- **Chemotherapeutic substance**: This refers to any chemical used to treat diseases, particularly infections.
- **Living organisms**: This indicates that the substance must be naturally occurring, not synthetic.
- **Inhibitory effect on parasitic organisms**: This means that the substance should either kill or inhibit the growth of parasites.

### Step 3: Evaluate the Options
1. **Exotoxin**: This is a toxin released by bacteria, which can harm the host but does not fit the definition of a chemotherapeutic agent derived from living organisms for treating parasitic infections.

2. **Bactericides**: These are substances that kill bacteria. While they are derived from living organisms, they specifically target bacteria, not parasites.

3. **Antibody**: Antibodies are proteins produced by the immune system to neutralize foreign substances. They are not chemotherapeutic agents in the traditional sense and do not fit the question's criteria.

4. **Antibiotic**: Antibiotics are substances that inhibit the growth of or kill microorganisms, including bacteria. They are derived from living organisms (like fungi and bacteria) and are used to treat infections, including those caused by parasites.

### Step 4: Conclusion
Based on the evaluation of the options, the correct answer is **Antibiotic**. Antibiotics are indeed chemotherapeutic substances derived from living organisms that can inhibit or kill parasitic organisms.

### Final Answer
The chemotherapeutic substance derived from living organisms that has an inhibitory effect on parasitic organisms is known as **Antibiotic**.

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