A) Lymph leaves the system of blood vessels through the capillaries due to blood pressure.
B) Lymph returns to the cardiovascular system through a network of open lymph capillaries and vessels that drain the tissues of lymph.
C) Valves inside the lymph vessels direct the flow of lymph in either direction.
D) Lymph vessels eventually drain into one of two collecting ducts, the thoracic duct and the right lymphatic duct.