Answer:
C. Yearly flu outbreaks have a negative effect on the US economy.
Explanation:
Which idea is explicitly stated in the article "What a Bad Flu Season Could Cost the US Economy"?
A. When people get the flu, they feel utterly miserable.
B. Vaccines will get more effective with future scientific advancements.
C. Yearly flu outbreaks have a negative effect on the US economy.
D. The flu vaccine is not reliable enough to be worthwhile
