As Many as 20% of All Americans Contract Influenza Each

Multiple Choice

As many as 20% of all Americans contract influenza each year. A sample of 400 randomly selected Americans is chosen and the number with influenza is recorded. Let X represent the number with influenza in the sample. What is the probability that, at most, 25% of the sample is observed to have influenza?

A) 0.0052
B) 0.0062
C) 0.9938
D) 0.9948