<prompt> True about the anatomy of great saphenous vein:Stas as a continuation of medial marginal veinEnds of femoral vein 2.5 cm below the inguinal ligamentThere are 2 - 5 valves below the knee.Ascends 2.5 - 3 cm behind tibial malleolus  <response>: A i.e. Stas as continuation- of medial marginal vein 