Which Item Best Describes Use of a Weapon of Mass

Multiple Choice

Which item best describes use of a weapon of mass destruction?

A) Death of 25 following an explosion in a chemical plant caused by faulty wiring
B) Death of 57 following nighttime tornadoes that struck a suburban area
C) Death of 49 people in a crowded mall following intentional dispersal of an unknown bacteria
D) Accidental release of radioactive gas from a nuclear power plant that has impacted thousands of people