Punctuation matters: What does this sentence mean?

What does this sentence mean?
Happy birthday to Besse Cooper, the world’s oldest person who turned 116 today.
a. It’s a birthday greeting for Besse Cooper. She is the oldest person in the world and she turned 116 today.
b. It’s a birthday greeting for Besse Cooper. She is the oldest person in the world and she is the eldest of some unspecified number of people who all turned 116 today.
Answer: b.
Explanation:
Besse Cooper actually turned 116 yesterday and the greeting went out on Twitter. You need to add a comma after “person” to indicate that “who turned 116 today” modifies Besse Cooper. The comma is what indicates a parenthetical phrase, so that the sentence means “Besse Cooper turned 116 today. She is the world’s oldest person.”
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