<prompt> Massive bleeding per rectum in a 70years patient is seen most commonly inCarcinomaColitisDiveiculosisPolyps  <response>: Hemorrhage from a colonic diveiculum is the most common cause of hematochezia in patients 60 years, yet only 20 of patients with diveiculosis will have gastrointestinal bleeding. Patients at increased risk for bleeding tend to be hypeensive, have atherosclerosis, and regularly use aspirin and nonsteroidal anti-inflammatory agents. Most bleeds are self-limited and stop spontaneously with bowel rest. The lifetime risk of rebleeding is 25.Reference: Harrison;s Principles of Internal Medicine; 19th edition; Chapter 353; Diveicular Disease and Common Anorectal Disorder 