Final answer:
The sentence that is punctuated correctly is: John F. Kennedy, a popular United States president, was known for his eloquent and inspirational speeches.
Step-by-step explanation:
The sentence that is punctuated correctly is John F. Kennedy, a popular United States president, was known for his eloquent and inspirational speeches. The correct sentence uses commas to set off the phrase 'a popular United States president' as well as the phrase 'John F. Kennedy,' providing additional information about him. Commas are also used to separate the adjectives 'eloquent' and 'inspirational.'
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