Which of the following is NOT a method to avoid contracting HIV/AIDS?

The correct answer highlights that sharing needles when injecting drugs is a behavior that significantly increases the risk of contracting HIV/AIDS. This action directly exposes individuals to contaminated blood, which is one of the primary transmission routes for the virus.

In contrast, the other choices presented are recognized strategies for reducing the likelihood of HIV transmission. Using condoms during sex serves as a barrier that helps prevent the exchange of bodily fluids, which can carry the virus. Being in a monogamous relationship with an uninfected partner minimizes the number of potential exposures to the virus. Regular testing for STDs is crucial as it helps identify infections early, allowing for timely treatment and reducing the chances of transmitting infections, including HIV.

Overall, the intent of the correct answer is to underline harmful practices that put individuals at risk, while the other options describe proactive measures to safeguard against HIV/AIDS contraction.