Why do doctors suggest that people get a flu vaccine each year?
Viruses replicate more rapidly over time. Viruses can mutate from year to year. Vaccines are absorbed by the body after a year. Vaccines get stronger over time.
Question: Why do doctors suggest that people get a flu vaccine each year?
A. Viruses replicate more rapidly over time.
B. Viruses can mutate from year to year.
C. Vaccines are absorbed by the body after a year.
D. Vaccines get stronger over time.
Answer: