Unknown General 0a1dcfb3 Best investigation for Diffuse Esophageal Spasm : A Enteroscopy B Manometry C Barium enema D Barium meal follow through High-Yield 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.