When the study of International Relations first began in modern times (1930s and forward), it was largely considered a theoretical discipline. The first two foundational volumes were, indeed, theoretically inclined: E.H. Carr’s The Twenty Years’ Crisis (1939) and Hans Morgenthau’s Politics Among Nations (1948). These were formative in the development of the theory of realism, as had been the prior works of Thucydides (The Peloponnesian Wars, in the mid-300s BCE), Thomas Hobbes (Leviathan, 1651) and Niccolò Machiavelli (The Prince, 1532). Realism focuses on how power contributes to a variety of political outcomes and to a state’s security, and by its assumptions, concludes there can be little security for any weak state (one with little power).

Both Carr and Morgenthau argued that the liberal internationalist worldview had been chiefly responsible for the crises of the inter-war years (between World War I and World War II) because that view ignored the ongoing struggle for power. Were a solution to be proposed to this focus of the international system (to ignore power accumulation and the struggles for security), it would be doomed to fail. The realist theories of Carr and Morgenthau also lacked the capacity to predict human behavior, according to those who critiqued them. Noam Chomsky, one of the more radical scholars, noted in 1994 that in international relations, ‘historical conditions are too varied and complex for anything that might be called ‘a theory’ to apply uniformly’ (quoted in Devetak, Burke, and George, 2011, 120).

As also understood from the information given, the correct answer is D. The statements with regard to the theory of realism in the option I “E.H. Carr’s The Twenty Years’ Crisis (1939) and Hans Morgenthau’s Politics Among Nations (1948). were formative in the development of the theory of realism.”, in the option II “Realism focuses on how power contributes to a variety of political outcomes and to a state’s security, and by its assumptions, concludes there can be little security for any weak state (one with little power).”, in the option III “The prior works of Thucydides (The Peloponnesian Wars, in the mid-300s BCE), Thomas Hobbes (Leviathan, 1651) and Niccolò Machiavelli (The Prince, 1532) were also formative in the development of the theory of realism.” and in the option V “The realist theories of Carr and Morgenthau also lacked the capacity to predict human behavior, according to those who critiqued them.” are correct. The statement in the option IV “Both Machiavelli and Hobbes argued that the liberal internationalist worldview had been chiefly responsible for the crises of the inter-war years (between World War I and World War II) because that view ignored the ongoing struggle for power.” is not correct because of the fact that both Carr and Morgenthau, not Machiavelli and Hobbes argued that the liberal internationalist worldview had been chiefly responsible for the crises of the inter-war years (between World War I and World War II) because that view ignored the ongoing struggle for power.