Final answer:
The Watergate Scandal led to President Nixon's downfall and resignation in 1974.
Step-by-step explanation:
The scandal that ultimately led to President Richard Nixon's downfall and resignation in 1974 was the Watergate Scandal. This scandal began with a break-in at the Democratic National Committee headquarters in the Watergate complex in Washington, D.C., by members of Nixon's re-election campaign. The subsequent investigation revealed widespread illegal activities, including attempts to cover up the involvement of Nixon and his advisors. The release of the White House tapes, which contained incriminating evidence, further implicated Nixon in the scandal and ultimately led to his resignation.
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