Final answer:
The United States won every major battle in the Mexican-American War.
Step-by-step explanation:
The Mexican-American War was a conflict between Mexico and the United States from 1846 to 1848. From the given options, it can be said that the United States won every major battle (option C). Mexico did not have greater economic advantages (option A) and they did not win every major battle (option B). Although the effectiveness of officers varied, there is no evidence to support that the United States had many poorly trained officers (option D).
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