The answer is usually D. rule by one person. An example of this would be one of the countries rules by a king such as 1700 Britain which was rules by King George, king of England around that time. Any of the Louis kings such as King Louis XIV of France in the 17th century. Another form of monarchy other than kings and queens would be emperors. An example of this would be the emperors of the Roman empire. Another form would be Napoleon Bonaparte but it was more of a dictatorship. A monarchy often describes a rule by one because of royal blood.