"The history of all hitherto existing societies is the history of class struggles." The preceding sentence is most closely associated with which of the following political theorists?

The statement "The history of all hitherto existing societies is the history of class struggles" is a seminal concept attributed to Karl Marx, primarily found in his work "The Communist Manifesto." This phrase reflects Marx's foundational belief that societal development and historical progress are heavily driven by the conflicts and dynamics between different social classes, particularly in the context of capitalism and the exploitation inherent in it.

Marx argued that every society throughout history has been marked by different forms of class struggle, whether that was between feudal lords and serfs, capitalists and workers, or among various other social classes. This idea is central to Marx's critique of political economy and his theory of historical materialism, which posits that material conditions and economic factors significantly shape the structure of society and its development over time.

The other theorists listed have different focuses and ideologies: Adam Smith is known for his contributions to economic theory and capitalism, emphasizing the invisible hand of the market rather than class struggle; V. I. Lenin expanded on Marxist thought for a political context, especially regarding revolution and socialism in Russia, but the statement itself is not primarily associated with his original writings; Niccolò Machiavelli is most recognized for his works on political power