Decoding symbols for Family Tree: Step-by-step Relationship Analysis: Break down the statement made by the boy: "He is the husband of my sister's mother's only daughter." • "My sister's mother" refers to the boy's own Mother. • "Only daughter of my mother" refers to the boy's Sister (since she is the only daughter in the family). • Now, replace that part in the sentence: "He is the husband of my Sister." Family Structure: Thus, the man is the Brother-in-law of the boy. Hence, the correct answer is "Option 2"