Which of the following United States Presidents served the shortest term in office?

The answer is William Henry Harrison because he served the shortest term in office due to his untimely death. Harrison was inaugurated as the 9th President of the United States on March 4, 1841, and unfortunately, he died exactly one month later, on April 4, 1841. He succumbed to pneumonia, which he likely contracted during his lengthy inauguration speech delivered on a cold and rainy day. Consequently, Harrison's presidency lasted only 32 days, making it the shortest in American history.