What causes AIDS (Acquired Immunodeficiency Syndrome)?

AIDS (Acquired Immunodeficiency Syndrome) is caused by the Human Immunodeficiency Virus (HIV). HIV attacks the immune system, specifically targeting CD4 cells, which are crucial for the body's ability to fight off infections and diseases. Over time, if untreated, HIV reduces the number of these cells, leading to a weakened immune response and eventually resulting in AIDS, where the body becomes vulnerable to opportunistic infections and certain cancers.

The other viruses listed, such as HBV (Hepatitis B Virus), the Influenza Virus, and the Herpes Virus, are associated with different diseases. HBV primarily affects the liver and can lead to conditions like hepatitis or liver cancer. The Influenza Virus is responsible for seasonal flu and respiratory infections, while the Herpes Virus can cause outbreaks of various types of herpes, including oral and genital infections. None of these viruses lead to AIDS, highlighting that HIV is specifically responsible for its development.