AIDS is transmitted through

Options

A. hand shake
B. countership
C. blood transfusion
D. all of above

Answer

### Step-by-Step Solution:

1. **Understanding AIDS**:
- AIDS stands for Acquired Immunodeficiency Syndrome. It is a condition caused by the Human Immunodeficiency Virus (HIV), which attacks the immune system, making the body more susceptible to infections and diseases.

2. **Modes of Transmission**:
- AIDS is primarily transmitted through specific behaviors and practices. The main routes of transmission include:
- **Sexual Contact**: This includes both heterosexual and homosexual relationships.
- **Blood Transfusion**: Receiving blood from an HIV-infected person can transmit the virus.
- **Sharing Needles**: Using needles or syringes that have been used by an HIV-infected person can also lead to transmission.

3. **Analyzing the Options**:
- **Handshake**: This is not a mode of transmission for AIDS. The virus cannot be transmitted through casual contact.
- **Counter Chip**: This term is unclear and does not relate to known modes of transmission for AIDS.
- **Blood Transfusion**: This is a well-known method of transmission for HIV, especially if the blood is from an infected individual.
- **All of the Above**: Since handshake and counter chip do not transmit AIDS, this option is incorrect.

4. **Conclusion**:
- Based on the analysis, the correct answer to the question "AIDS is transmitted through" is **blood transfusion**.

### Final Answer:
AIDS is transmitted through **blood transfusion**.

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