Which of the following is odd one for transmission of HIV infection

Options

A. It is spread by mere touch or physical contact
B. By the transfusion of contaminated blood and blood products
C. By sharing infected needles as in the case of intravenous drug abusers
D. From infected mother to her child through placenta

Answer

To determine which option is the odd one out for the transmission of HIV infection, we need to analyze the common methods of HIV transmission and identify the one that does not fit.

### Step-by-Step Solution:

1. **Understanding HIV Transmission**:
- HIV (Human Immunodeficiency Virus) is primarily transmitted through specific routes. The main modes of transmission include:
- **Contaminated Blood**: Sharing or receiving blood that has the virus.
- **Infected Needles**: Sharing needles among intravenous drug users.
- **Unprotected Sexual Contact**: Engaging in sexual activities without protection with an infected person.
- **Mother to Child**: Transmission can occur from an infected mother to her child during childbirth or breastfeeding.

2. **Analyzing the Options**:
- We need to compare the provided options for transmission methods against the established methods of HIV transmission.
- The options typically include:
- A) Spread by mere touch or physical contact
- B) Sharing contaminated blood
- C) Sharing infected needles
- D) Unprotected sexual contact
- E) Mother to child transmission

3. **Identifying the Odd One Out**:
- Among the options, A) "Spread by mere touch or physical contact" does not represent a recognized method of HIV transmission. HIV is not transmitted through casual contact such as touching, hugging, or shaking hands.
- The other options (B, C, D, and E) are valid methods of HIV transmission.

4. **Conclusion**:
- Therefore, the odd one out for the transmission of HIV infection is option A) "Spread by mere touch or physical contact".

### Final Answer:
The odd one for transmission of HIV infection is **A) Spread by mere touch or physical contact**.