Answer:
A. It led to strong public support for U.S. entry into the war.
Step-by-step explanation:
The Zimmermann Telegram was essentially a telegram sent from Germany to Mexico, in which to ask for the assistance of Mexico's help for the Central Power. In return, after the war Germany would assist Mexico in reclaiming the lands that they lost during the Texas Independence and Mexican-American War. However, Mexico disregarded the message and sent it to the US, which caused public outrage and strong support for the Allied side.
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