Once the activity of americium in a smoke detector falls below 5 percent of its original activity, it's no longer able to effectively detect smoke and trigger the alarm. If the half-life of americium-241 is approximately 432.2 years, how many years will it take before the americium-241 is unable to detect smoke? Question 11 options:

A)

10 years

B)

20 years

C)

1,868 years

D)

2 years