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: Surgery
All of the following are true about achalasia cardia except: March 2012 
Select and explain. 
A. Bird beaks appearance, B. Absent air bubble in stomach, C. Decreased lower oesophageal sphincter tone, D. Absent peristalsis in the body of oesophagus
C: Decreased lower oesophageal sphincter tone
Answer: C: Decreased lower oesophageal sphincter tone 
Explanation: Ans: C, Decreased lower oesophageal sphincter toneAchalasia cardiaBarium radiology may show a tapering stricture in the distal oesophagus, often described as a 'bird's beak'. The gastric bubble is usually absent.The physiological abnormalities in achalsia cardia are non-relaxing LOS (lower oesophageal sphincter) and absent peristalsis in the body of the oesophagus.