It is possible to explain, analyze and understand the international security in six levels:

• Individual level: Security for the individual.

• Societal level: Security for the social group, i.e. ethnic, national, religious, linguistic, or community groups.

• National level: Security for the state or nation.

• Regional level: Security for the region, that is, a coherent security region.

• International level: Security for the international society, the society of nations, and most states in the world.

• Global level: Security for the planet Earth and space. 

Therefore, the correct option is C.

The right of self-defense is enshrined in Article 51 of the UN Charter.

Critical Security Studies (CSS) is an umbrella term for a range of approaches which seek to challenge the orthodoxy of ‘traditional’ security studies. Critical approaches apply post-positivist perspectives such as critical theory and post-structuralism and change the referent object of security.

The traditionalist security approaches have the following features: First, they have mostly emphasized the military aspects of security as well as the concepts such as war, defense, strategy, and geopolitics. They have focused on the problem of national security and the nation-state. Second, the traditionalist security approaches mostly choose a narrow or mono-sectoral agenda and attach priority to one sector (military), one actor (the state), and one action (the use of force). Finally, the traditionalist security approaches have a statist perspective, which is based on a scientific and objectivist understanding of knowledge.

The Boxer Rebellion in China in 1900 is an example to give for the ancestors of peace operations before the League of Nations.

Sovereignty means a central governing authority within a specified geographical territory.

Structural realism emphasizes four core elements of international politics:

• States are seen as rational actors and by far the most important actors in the international system.

• The international system is anarchic; there is no international authority that can prevent the use of force between states.

• Each state cannot take its security for granted and thus, is responsible for ensuring its own survival, most notably through the nurturing of material capabilities.

• The balance of power (the formation of alliances with certain states to counter the threat of other states) is the defining mechanism that regulates the international system and explains war and peace

Hard power is the ability of one actor (usually but not necessarily a state) to influence another through the use of threats or rewards, typically involving military ‘sticks’ or economic ‘carrots’.

The UN Transitional Administration in East Timor is an example of the fourth generation peacebuilding.

Conflict intervention methods consist of the following: Conflict prevention, conflict management, conflict settlement, conflict resolution, conflict transformation, and conflict provention. 

From 1948 onwards the UN has established seventy-one peacekeeping missions in various geographies to address many different problems. Therefore, the correct option is C.

The stress on interdependence that is basic to commercial liberalism has been further developed by neoliberals into what Keohane and Nye (1977) called complex interdependence. Complex interdependence reflects the extent to which peoples and governments in the modern world are affected by what happens elsewhere, and particularly by the actions of their counterparts in other countries. This applies not only in the economic realm, through the advance of globalization, but is also evident in relation to a range of other issues, including climate change, development and poverty reduction, and human rights.