<prompt> All the following are false about houstons valve except:They disappear on distensionThey contain all layers of muscle layerPlaced transverselyMiddle valve is the most constant and fold towards right side  <response>: The transverse folds of rectum or Houstons valves are semi-lunar transverse folds of the rectal wall that protrude into the rectum, not the anal canal as that lies below the rectum. CHOICE EXPLANATION ELIMINATION REASON 1 False statement. Prominent on distension 2 False statement. Contains only circular muscles 3 True statement.Placed transversely 4 False statement. Middle valve constant and fold towards left side 