Dane Archer and Rosemary Gartner (1976,1984)found in a Cross-Cultural Study

Dane Archer and Rosemary Gartner (1976,1984) found in a cross-cultural study of war and domestic crime rates,that being at war is correlated with increased domestic homicide rates.Why?

A) Countries at war tend to have more aggressive citizens.
B) Post-traumatic stress syndrome (PTSD) contributes to the homicide increase.
C) War leads to bloodlust.
D) Returning veterans have been inured to violence and trained to kill.
E) War serves to legitimize violent solutions to social problems.