Foreign  policy is “the actions of an independent political authority’ because it is reserved to sovereign states.” However, foreign policy decisions are not made in an “international” vacuum. There is a strong domestic dimension of every foreign policy decision. As representatives of different states are displaying foreign policy behavior, they also have to market their “international” decisions and actions to their domestic stakeholders and constituencies. The direct result of this phenomenon is a broader decision-making process. As such “foreign policy-making will not be restricted to “traditional” foreign policy actors only and that other bureaucracies will become involved”, and even “actors from other countries may have an impact on the politics surrounding foreign policy making.” Hence, the study of foreign policy represents a challenge to understand how states, institutions and peoples engage amongst themselves both within, and with, a vibrant and complex international system.

As can be understood from the information given, the correct answer is E. All statements in the options can be used to affirm the argument “the study of foreign policy represents a challenge to understand how states, institutions and peoples engage amongst themselves both within, and with, a vibrant and complex international system.”