Meckel's diverticulum is an outpouching of which part of the intestine?

Meckel's diverticulum is an outpouching that occurs in the distal ileum, which is the lower part of the small intestine. This congenital abnormality can result from the incomplete closure of the omphalomesenteric duct (or vitelline duct), a remnant of embryonic development. As a result, Meckel's diverticulum typically measures a few centimeters in length and is located about 2 feet from the ileocecal valve.

Understanding that Meckel's diverticulum arises from the distal ileum is crucial since it can sometimes be associated with heterotopic tissue, which may lead to complications such as gastrointestinal bleeding or obstruction. This association further emphasizes the importance of recognizing the location of Meckel's diverticulum in the ileum rather than any other part of the intestine, such as the jejunum or colon. Thus, the characteristic position within the distal ileum makes this option the correct answer.