This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urology, Subject name: Surgery
Pseudoachalasia may be caused by 
Select and explain. 
A. Gastric adenocarcinoma, B. Lung carcinoma, C. Pancreatic carcinoma, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Pseudoachalasia is an achalasia-like disorder with dysphagia and weight loss that is usually produced by adenocarcinoma of the cardia, but has also been described in relation to benign tumours at this level. It has been presumed that the inability of the sphincter to relax is linked to the loss of body peristalsis, but other cancers outside the oesophagus (bronchus, pancreas) have also been associated with pseudoachalasia.Reference : page 1036 Bailey and Love's sho practice of surgery 25th edition