How Are Civil Wars Different from Interstate Wars

How are civil wars different from interstate wars?

A) Civil wars tend to be more violent than interstate wars.
B) Interstate wars are between two countries, and civil wars are conflicts within a single state.
C) Civil wars always use guerrilla warfare, whereas interstate wars always use traditional methods.
D) Civil wars tend to be less violent than interstate wars.
E) Interstate wars tend to last longer than civil wars.