<prompt> Investigation of choice for Zenkers diveiculum is:CECTEndoscopyEsophageal manometryBarium Swallow  <response>: Ans is d i.e. Barium Swallow Once suspected, the diagnosis is established by a barium swallow. Endoscopy is usually difficult in the presence of a cricopharyngeal diveiculum, and potentially dangerous, owing to obstruction of the true esophageal lumen by the diveiculum and the attendant risk of diveicular peiforation.- Schwaz 