This cloze test question requires the word that correctly fills gap 15. The passage discusses the United Nations Security Council and the measures it can take to maintain or restore international peace and security.
The correct word is sanctions. Under Chapter VII of the UN Charter, the Security Council can impose sanctions on states or entities that threaten international peace. These may include economic sanctions (trade restrictions, asset freezes), diplomatic sanctions (severing of relations), or other non-military measures outlined in Article 41. Sanctions are the primary enforcement tool the Council uses before resorting to military action.
The other options do not fit the context of UN enforcement:
"Rules" are general guidelines or regulations, not specific enforcement measures imposed on violators.
"Order" could refer to a legal order but is not the standard term for the punitive measures the Security Council imposes.
"Discipline" implies internal correction or punishment, which does not describe the external enforcement measures applied between sovereign states.