Answer:
Option A, Mexican treatment of American diplomats, was NOT a cause of or justification for the Mexican-American War.
Step-by-step explanation:
Although there were some incidents of violence against American diplomats in Mexico, they were not the main reason for the war. The main causes were the annexation of Texas by the United States, which Mexico saw as an illegal land grab, and disputes over the border between Texas and Mexico. The issue of unpaid Texas war reparations was also a contributing factor, but it was not the primary cause of the war. The United States also engaged in provocative troop deployments, particularly along the disputed border region, which further escalated tensions between the two countries.
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