In functionalist approach, society is evaluated in terms of basic needs. The state has emerged as a necessity within the society. These needs are:

1. Maintaining order: State’s most important function in a given society is maintaining order. The state holds the legitimate power in order to maintain and keep the social and political order when needed.

2. Relations with other states/governments: In a more globalized world, interrelations of the states are crucial. Economic relations require political relations. Thus, economic agreements, military agreements, diplomatic affairs and even due to compelling reasons, war might be a result for relations with other states/government.

3. Directing the system: Society is a complex social, economic and political system. Thus, the state is responsible for governing this complex system. One of the function of the state is to resolve possible problems that occur in this complex system.

Therefore, the correct option is A