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
[{'content': 'Sigmoid volvulus rotation occurs: \nSelect and explain. \nA. Clockwise, B. Anticlockwise, C. Both clock wise and anti clock wise, D. Axial in direction', 'role': 'user'}, {'content': 'Answer: B \nExplanation: (Anti-clock wise) (1197-Baily & Love 24th) (1192-B &L 25th)SIGMOID VOLVULUS - Most common cause of large bowel obstruction in indigenous black Africans.* Rotation nearly always occurs in an anticlockwise direction* Predisposing causes - Band of adhesions (Peridiverticulitis) overloaded pelvic colon, Long pelvic mesocolon, narrow attachment of pelvic mesocolon.* Plain X-ray film of abdomen - The distended loop may assume a \'coffee bean\' shape.* In caecal volvulus the concavity of the "coffee bean\' points towards the right lower abdominal quadrants and in sigmoid volvulus it points towards the left lower quadrants.* On barium enema, "bird\'s beak" or "ace of spades" deformity with spiral narrowing of the upper end of the lower sigments is pathognomic (739-CSDT 11th)', 'role': 'assistant'}]