Which of the following statements about 'Valves of Houston' is true -
Valves of Houston are lost after full mobilization of the Rectum.
The middle valve is located on the Right Wall but corresponds to the middle convex fold to the left.
The middle valve (and not upper valve) corresponds to the level of peritoneal reflection.
Valves of Houston do not contain all three layers of the muscle wall.
The middle valve corresponds to the middle convex fold to the Right
The upper valve corresponds to peritoneal reflections
The valves contain all three layers of muscle wall
Valves disappear after mobilization of Rectum.