Answer:
b.A telegram was intercepted that stated Mexico would get lands back if they allied with Germany against the United States
Step-by-step explanation:
The two main reasons that the United States joined the War on the Allied side is because of:
1) The sinking of Lusitania, in which there was 128 US citizens on board,
and,
2) The Zimmermann Telegram, in which Germany called for aid from Mexico, in exchange for them helping Mexico retake the lands that they lost in the Texas Independence and the Mexican-American war.
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