How is an oilgarchy different from a monarchy? A) Historically, oligarchies tended to replace monarchies as a common form of government B) Oilgarchies are only a theory, while monarchies have been around for thousands of years C) oligarchies are rule but the few people or a small group, while monarchies are usually ruled by one person. D) historically, oligarchies were mostly found in asian areas while monarchies were the only form of european government