US Health Officials Are Considering Different Ways of Preparing for a Future

U.S. health officials are considering different ways of preparing for a future worldwide epidemic of human influenza that could be derived from a form of the disease that infects birds (avian flu) . Which of the following actions would be useful in preventing a future influenza epidemic?

A) Inject helper T cells into healthy people to boost immune systems.
B) Inoculate infected people with a vaccine against the pathogen.
C) Give antibiotics to people with mild symptoms.
D) Ask people with flu symptoms to stay at home.