This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
[{'content': 'All of the following statements stand true for telengiectasia of colon except : \nSelect and explain. \nA. May be seen in person less than 40 years of age, B. May be seen in person more than 60 years of age, C. Common site is caecum, D. 50% involve rectum', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Answer is D (50% involve rectum) Thus involvement of left side of colon (or rectum) is uncommon and ceainly less than 50% of cases involve rectum. Telengicctasias consist of dilated capillaries that appear clinically as erythematous to violaceous vessels. Telengiectaseas in colon may most commonly be due to: 1. Vascular ectasia / Angiodysplasia - Angiodysplasia is a telengiectasia of thin walled capillaries and venules in the mucosa and submucosa of colon - Mean age at diagnosis is approx. 65 years but cases have occured in the young. - 2/3 of lesions are located in coecum and ascending colon and one quaer in the left colon. 2. Radiation : Telengiectaseas are the most common long term effect of radiation. 3. Hereditary hemorrhagic telengiectaseas -affect younger patients with a positive family history.', 'role': 'assistant'}]