Augustin de Iturbide was able to declare independence from Spain while also proclaiming himself emperor in part because

Iturbide’s Plan of Iguala helped unite royalists and independence supporters by promising an independent Mexico under a monarchy. Many colonists were accustomed to Spanish rule by a king, so a monarchy seemed familiar and acceptable to some. This helps explain how he could declare independence while also proclaiming himself emperor; choice C identifies that familiar form of government.

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