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: Unknown
Best investigation for Diffuse Esophageal Spasm : 
Select and explain. 
A. Enteroscopy, B. Manometry, C. Barium enema, D. Barium meal follow through
B: Manometry
Answer: B: Manometry 
Explanation: Ans- B Manometry For Motility disorders:: First line is UGIE IOC IS Manometry For GERD::1st line is UGIE IOC :24 hr ambulatory pH measurement.