A. She should not have another dose of influenza vaccine, because her reaction would be likely to recur.

Not really. If this really was an allergic reaction to the vaccine, you might expect to have a recurrence. However, but "response" was not allergic. In fact, her post-vaccination illness was not a response to the vaccine at all. Remember that the injectable influenza vaccine is inactivated. So it cannot give the patient "the flu". Some vaccine recipients may experience transient fever as a reaction to the vaccine, but this rarely last more than 24 hours. In this case, the patient got her vaccine too late. She had the misfortune of contracting wiltype influenza before the vaccine immunity could take effect. So, she had "the flu" all right, but not from the vaccine -- in spite of it!