In Late 2001, a Number of American Citizens Died from Anthrax

In late 2001, a number of American citizens died from Anthrax poisoning that caused widespread fear amongst citizens. What is the best reason why widespread distribution of antibiotics was not recommended?

A) Antibiotics are not used to treat anthrax exposure
B) This is a very expensive course of treatment
C) Indescriminate use may cause significant side effects
D) Overuse of antibiotics could result in a resistant strain of the agent