I think it would be To Whom It May Concern, because you don't know their relationship status (if that makes any sense)
I could be wrong though...
Answer:
A) A person born in the U.S. whose parents are citizens of another country.
Okay so matching the words to the definition am I correct let me know so I can help I just wanna make sure
C -- there is no evidence in the passage to support any other answer but this one
