All of the Following Are Ways Collective Security Organizations Improve

All of the following are ways collective security organizations improve the chances of peace EXCEPT:

A) providing neutral soldiers to be a buffer between hostile and suspicious states.
B) intervening to repel an invasion when the invading countries are great powers.
C) organizing economic sanctions against a state that has unlawfully attacked another state.
D) offering mediators to help states find mutually acceptable solutions.
E) sending soldiers to a country to oversee disarmament agreements.