Interferons act against viral infection by

Options

A. Protecting other cells against virus
B. Functioning as macrophages
C. Providing antibodies
D. Directly destroying genetic material of virus

Answer

### Step-by-Step Solution:

1. **Understanding Interferons**: Interferons are a type of antiviral protein that play a crucial role in the immune response against viral infections. They are produced and secreted by cells that have been infected by viruses.

2. **Mechanism of Action**: When a cell is infected by a virus, it releases interferons as a warning signal to neighboring uninfected cells. This signaling helps to prepare these adjacent cells to defend themselves against potential viral infection.

3. **Inducing Protective Mechanisms**: The neighboring cells, upon receiving the interferon signal, begin to produce proteins that inhibit viral replication. Specifically, they produce translation-inhibiting proteins that prevent the virus from synthesizing its proteins, thereby limiting its ability to replicate.

4. **Evaluating the Options**:
- **Option A**: Protecting other cells against the virus - This is correct. Interferons help neighboring cells to develop resistance to the virus.
- **Option B**: Functioning as macrophages - This is incorrect. Interferons do not act as macrophages; instead, they can activate macrophages.
- **Option C**: Providing antibodies - This is incorrect. Antibodies are produced by plasma cells, not by interferons.
- **Option D**: Directly destroying genetic material of the virus - This is incorrect. Interferons do not directly destroy viral genetic material.

5. **Conclusion**: The correct answer to the question is **Option A: Protecting other cells against the virus**. Interferons play a protective role by signaling neighboring cells to prepare for potential viral attacks.