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
Which drug is used for Achalasia cardia- 
Select and explain. 
A. Nifedipine, B. Propranolal, C. Atenolol, D. Bethnecol
A: Nifedipine
Answer: A: Nifedipine 
Explanation: None