This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Small & Large Intestine, Subject name: Surgery
Following is least common about angiodysplasia of colon: 
Select and explain. 
A. Involvement of cecum, B. Involvement of rectum in 50% of cases, C. Affecting age group >40 years, D. Cause of troublesome lower GI hemorrhage
B: Involvement of rectum in 50% of cases
Answer: B: Involvement of rectum in 50% of cases 
Explanation: Ans. (b) Involvement of rectum in 50% cases* Angiodysplasia is rare in rectum* Causes troublesome intermittent lower GI bleeding. Very difficult to diagnose