Annual flu shots work by:
Question 1 options:
increasing the volume of lymph,
increasing the number of white cells,
increasing the number of specific antibodies,
introducing a relatively innocuous virus to fight off a more dangerous virus.
Answer is introducing a relatively innocuous virus to fight off a more dangerous virus. Flu shot is a vaccine, during which inactivated virus is injected into the human organism to allow for the formation of immunity against the disease.