Bajpai is the maternal uncle of the man in the photograph.

Step‑by‑step reasoning

Break the sentence into parts:

  • “The father of my brother” → that is Bajpai’s father (same father for both brother and Bajpai).
  • “The only daughter of the father of my brother” → the only daughter of Bajpai’s father → that is Bajpai’s sister.
  • “The son of the only daughter of the father of my brother” → the son of Bajpai’s sister → that is Bajpai’s nephew.

So the man in the photograph is Bajpai’s nephew.
If Bajpai is male, then Bajpai is the maternal uncle of that man; if Bajpai is female, she is the maternal aunt.

Typical exam answer

In standard reasoning tests, Bajpai is treated as male, so the expected answer is:

  • Maternal uncle of the man in the photograph.

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