Final answer:
The United States instigated the Six-Day War by informing Israel of an impending attack by Syria.
Step-by-step explanation:
The correct answer is C. It instigated the war by informing Israel that Syria was preparing to invade. In the Six-Day War, which took place from June 5 to June 10, 1967, the United States played a role in instigating the war by providing intelligence to Israel that Syria was planning an attack. This information was a key factor in Israel launching preemptive strikes against Egypt, Syria, and Jordan.
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