3. what kept the peace in europe until 1914 despite the rapid buildup of armies and weapons?

a. a system of military alliances that divided europe into two camps

b. a system of peace treaties that invoked harsh penalties for aggressor nations and their allies

c. the knowledge that if any one nation declared war on another, all nations would rise against the aggressor

d. the introduction of new weapons and methods of warfare that made war hard to win