Lung cancer is most often caused by exposure to tobacco smoke.
Tobacco is smoked in pipes or in cigarettes or bidis.
Lung cancer is most often caused by cigarettes.
What is lung cancer most often caused by?
(A) the Moon
(B) Pollution
(C) sunlight
(D) Chemical energy
(E) fossil fuels
(F) cigarettes
(G) burning
(H) marijuana smoke