text: In the circulatory system, a<unk>  is a blood<unk> essel that carries blood toward the heart. The majority of<unk> s in the body carry low-oxygen blood from the tissues back to the heart; the exceptions being the pulmonary and umbilical<unk> s which both carry oxygenated blood.
option_0: Vein
option_1: Bite
option_2: Iodoform
option_3: Wart
option_4: Nylon
option_5: Cineole
option_6: Hydrocarbon
option_7: Oxamyl