A man: "She is the daughter of my mother's only son": how is the girl related to him

The same question, asked 2 times: 12 Sep 2025 S3, 16 Sep 2025 S1. Every wording below, oldest first.

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Question 1
12 Sep 2025 S3
20 $Pointing to a girl, a man said, "She is the daughter of my mother’s only son." How is the girl related to the man?$
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Question 2
16 Sep 2025 S1
21 $Pointing to a photograph, a man says, "She is the daughter of the only son of my father's wife". Who is the woman to the man?$
Tap an option to check your answer.