karl marx was an influential german thinker and revolutionary who pioneered the idea of capitalism…

Brief Explanations:

Karl Marx is well - known for his contributions to the theory of communism. He analyzed the contradictions of capitalism and proposed a vision of a class - less society under communism. Utopianism is a more general idealistic concept, mysticism is related to spiritual and esoteric beliefs, and capitalism is the system he critiqued.

Answer:

C. communism