Which sentence shows the correct use of commas?

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2 points
Hannah visited Mexico, Maine, and Miami on her summer vacation.
Olivia wanted to go to Maine with Hannah but she decided to save money, instead.
Leo on the other hand went to New York, and Key West.
Nylah, Mya's younger sister decided to take her dog Skai to the dog park, once, a week during the summer.

Hannah visited Mexico, Maine, and Miami on her summer vacation.