When a plant/animal is infected with virus, it may produce an antiviral substance that is capable of inhibiting the multiplication of that virus. Identify the correct name of this substance

Options

A. Virion
B. Antivirion
C. Antigen
D. Interferon

Answer

To solve the question regarding the antiviral substance produced by plants or animals when infected with a virus, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the name of the antiviral substance that inhibits the multiplication of viruses in infected plants or animals.

2. **Analyzing the Options**: The options provided are:
- A) Virion
- B) Antiviron
- C) Antigen
- D) Interferon

3. **Defining Each Option**:
- **Virion**: This refers to a complete virus particle that consists of genetic material and a protein coat. It does not inhibit viral multiplication.
- **Antiviron**: This term is not commonly used in virology and does not refer to a known antiviral substance.
- **Antigen**: Antigens are substances that induce an immune response, but they do not specifically inhibit viral replication.
- **Interferon**: Interferons are proteins produced by host cells in response to viral infections. They play a crucial role in the immune response by signaling neighboring cells to enhance their antiviral defenses.

4. **Identifying the Correct Answer**: Based on the definitions, interferons are the correct answer as they are specifically known for their role in inhibiting viral replication and enhancing the antiviral response.

5. **Conclusion**: Therefore, the correct name of the antiviral substance that inhibits the multiplication of the virus is **Interferon**.

### Final Answer:
The correct answer is **Interferon** (Option D).

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