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The correct answer to the question is:
D) Death of Warren G. Harding
Explanation:
1. The event that marked the end of the Harding administration and the beginning of the Coolidge administration was the death of Warren G. Harding.
2. Warren G. Harding, the 29th President of the United States, passed away on August 2, 1923, while in office.
3. Calvin Coolidge, who was the Vice President at that time, succeeded Harding as President following his death.
This transition from Harding to Coolidge due to Harding's death led to the start of the Coolidge administration.
