Which Is the Best Scientific Explanation for the Increasing Concern

Multiple Choice

Which is the best scientific explanation for the increasing concern over the recent outbreaks of avian influenza in Hong Kong and other Asian locations

A) avian influenza may infect humans.
B) human influenza viruses may exchange genetic material with avian influenza viruses and infect humans more efficiently.
C) avian influenza may spread to other countries.
D) avian influenza may change to another virus that could infect humans.