Assess the Following Statements and Determine Which One Is Incorrect

Assess the following statements and determine which one is incorrect regarding antigenic shift.

A) The influenza virus genome mutates over time changing the amino acid sequence of the envelope glycoproteins.  Each encounter with a new version of the virus requires activation of naive lymphocytes rather than memory cells,which is the reason we receive a new vaccination each year.
B) The influenza genome contains 10 genes distributed on 8 separate RNA strands.  These strands can be exchanged between different viruses.
C) Some virus strains infect birds and swine,some infect swine and humans.  If the strain that infects swine and humans exchanges strands with a bird flu strain while in a swine host cell,that virus can go on to infect a human who will have no recognition for the bird protein.
D) If a new strain of virus emerged from an antigenic shift event,a vaccine different to the annual flu vaccine would have to be administered because the proteins coded for by the new strain would be different to those made as a result of antigenic drift.