Final answer:
The correct sentence that uses an apostrophe is 'Originally, the Louvre was constructed as the French royals' residence.'
Step-by-step explanation:
The sentence that uses an apostrophe correctly is: Originally, the Louvre was constructed as the French royals' residence. The apostrophe is used to indicate possession by the French royals. In this sentence, the apostrophe is placed after the word "royals" because there is more than one royal.
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