When preparing for an emergency bioterrorism drill, the nurse instructs the drill volunteers that each biological agent requires specific client management and medications to combat the virus, bacteria, or toxin. Which statement reflects the client management of variola virus (smallpox)?(A) A vaccination is effective only if administered within 12 to 24 hours of exposure.(B) Smallpox spreads rapidly and requires immediate isolation.(C) Acyclovir is effective against smallpox.(D) Smallpox is spread by inhalation of spores.