Which microorganism causes Hepatitis B?

Hepatitis B is caused by the [A] Virus. Specifically, it is a member of the Hepadnaviridae family. This viral infection primarily targets the liver, leading to inflammation and potentially serious liver damage. Hepatitis B virus (HBV) is transmitted through contact with infected blood or bodily fluids, such as during unprotected sexual activity, sharing needles, or from an infected mother to her baby during childbirth. Unlike protozoa [B] or bacteria [C], which do not cause hepatitis B, HBV is a small, enveloped DNA virus known for its ability to persist in the body, sometimes leading to chronic hepatitis and long-term complications.