Cork screw appearance on radiography is seen in-

Ans. is 'd' i.e., Diffuse esophageal spasm * "Cork screw esophagus" on barium study is seen in diffuse esophageal spasm.* In diffuse esophageal spasm, barium swallow shows that normal sequential peristalsis below the aortic arch is replaced by uncourdinated simultaneous contractions that produce the appearance of curling or multiple ripples in the wall, sacculation and pseudodiverticula - the "Corkscrew" esophagus.