According to Constructivists, What Explains the Considerable Effort Put Forth

According to constructivists, what explains the considerable effort put forth by the United States to try to obtain UN Security Council approval for the 2003 Iraq War?

A) the socialization that international institutions like the United Nations play a key legitimizing role in international relations
B) to obtain military support from other states for its invasion
C) the belief that collective security is the only way military efforts can be successful in the international system today
D) to mask its imperial capitalist intentions
E) to avoid economic sanctions from the United Nations for violating international law by invading Iraq