Five years after quitting smoking, which statement best describes the change in cancer risk relative to a current smoker?

• A. Tenfold decrease
• B. No change
• C. Fivefold decrease
• D. Twofold increase

Answer: (A)

Quitting smoking removes ongoing exposure to cancer-causing substances, so the risk begins to fall once the body stops taking in tobacco. By five years after stopping, cancer risk is greatly lower than in someone who continues to smoke. The tenfold decrease illustrating this gap is a way to express how much the risk declines when the harmful exposure is removed and the body starts repairing damage. Of course, the exact amount varies by cancer type and individual factors, and risk does not typically drop to the level of a never-smoker within just five years.