PT 30 S4 Q4

A certain gene can be stimulated by chemicals in cigarette smoke, causing ... ...

If the statements above are true, it can be concluded on the basis of them that
(A) stimulation of the gene by chemicals in cigarette smoke is not the only factor affecting the risk for smokers of developing lung cancer
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Practice Set: "Drawing Conclusions" Questions, Set 1