<prompt> In Carpal tunnel syndrome, features are of -Compression of ulnar nerveCompression of median nerve under the flexor retinaculumAnaesthesia over thenar eminenceAtrophy of hypothenar muscles  <response>: The carpal bones form an arch which is convex on the dorsal side of the hand and concave on the palmar side.The groove on the palmar side is covered by flexor retinaculum, thus forming carpal tunnel.Carpal tunnel syndrome is caused by compression of median nerve. 