Correct Answer: Saphenous vein

Solution : The correct option is the Saphenous vein .

The saphenous vein is the longest in the human body. It is a significant superficial vein in the lower limb that runs the length of the leg. The large saphenous vein is responsible for returning blood from the lower limbs to the heart. It starts on the medial side of the foot and runs up the leg along the inner thigh before joining the femoral vein in the groin region.