Which organ is primarily affected by peritonitis?

The correct choice focuses on the abdominal cavity, which is directly affected by peritonitis. Peritonitis is an inflammation of the peritoneum, the membrane lining the abdominal cavity and covering the abdominal organs. When an infection or irritation occurs in this area, it leads to a significant inflammatory response that can impact the function and health of various organs situated within the abdominal cavity.

While the liver, kidneys, and pancreas can experience complications as a result of peritonitis, they are not the primary structures involved in the condition itself. The peritoneum is crucial because it houses and protects the organs in the abdominal cavity, and any infection or inflammation affecting this membrane creates a systemic reaction that can affect the entire abdominal area and can lead to serious complications. Thus, recognizing that peritonitis is fundamentally an issue with the abdominal cavity provides a clearer understanding of the condition and its implications.