In general, there are two or three levels such as system and state or system, state and individual. In case the system approach is used, then the structure becomes the main focus to emphasize and the features of each state and their decision makers or power capabilities are not taken into consideration. In other words, in such cases, public opinions, local characters, ethnic or ideological differences are not a point of concern for the researcher. Hence, in system theories, state is accepted as an entity responding to the effects from outside whereby internal features are ignored. In these models based on the system level of analysis, foreign policy is accepted as a response of state to the foreign environment.On the other hand, in the case of state level analysis, according to the theoretical framework used, state is accepted as the main determinant for foreign policy process and in some theories such as game theories, state is assumed to maximize its gains, but for realist theories state takes balance of power into consideration and tries to attain more power to survive. Taking the states to the core of research as mentioned above provides the researcher the opportunity to make concrete generalizations.Theories only focusing on individuals such as decision making theories and its models, foreign policy process is tried to be analyzed through behaviors of decision makers or political leaders. In this kind of analysis, individual is very central and also ideologies, motivations, values and beliefs are very important factors to be included to the analysis. The correct answer is C.