Inflammation of which part of the body is typical in ulcerative colitis?

Ulcerative colitis is characterized by inflammation specifically in the rectum and colon. It is a form of inflammatory bowel disease (IBD) that primarily affects the mucosal layer of the gastrointestinal tract, beginning in the rectum and potentially extending proximally to involve part of or the entire colon. The hallmark symptoms are abdominal pain, diarrhea, and rectal bleeding.

The other options pertain to areas that are not typically involved in ulcerative colitis. For instance, the stomach is associated with conditions like gastritis, while the small intestine is more commonly affected in Crohn's disease, another type of inflammatory bowel disease. The liver, although it plays a role in metabolism and digestion, is not a direct site of inflammation in ulcerative colitis, though it can exhibit secondary effects in severe cases. Therefore, inflammation in the rectum and colon is the defining feature of ulcerative colitis, making it the correct answer.