单项选择题
A.are responsible for 84,000 deaths each year. B.are strongly linked to cigarette smoking. C.are strongly linked to lung cancer. D.result in 30 per cent of deaths per year.
A.inhibits the flow of oxygen to the heart. B.increases absorption of other smoke particles. C.inhibits red blood cell formation. D.promotes nicotine absorption.
A.blood circulation through the body. B.activity of other toxins in the blood. C.formation of blood clots. D.an increase of platelets in the blood.