Question

Which sentence is punctuated correctly?

Tanna president of the National Honor Society truly enjoys volunteer work.
The old house, that my father grew up in, is being completely renovated.
My sister, who is a waitress at Billy’s Big Burger Shack, is sixteen years old.
The bird that built a nest in the oak tree, appears to have an injured wing.
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Answer 1

The third sentence is correct:

"My sister, who is a waitress at Billy’s Big Burger Shack, is sixteen years old."

Explanation: the clause "who is a waitress at Billy’s Big Burger Shack" is nonrestrictive (extra information) and is correctly set off with commas; "who" is correctly used for a person.