A 5-year-old boy presents with obesity, intellectual disability, hypotonia, and hyperphagia. Genetic analysis reveals a deletion on chromosome 15 that was inherited from his father. This clinical presentation is most consistent with which genetic disorder?

✓ Correct Answer: Option B

Prader-Willi syndrome is caused by the loss of function of specific genes on chromosome 15 (15q11-q13), typically due to a paternal deletion or maternal uniparental disomy. It is characterized by hypotonia, hyperphagia leading to obesity, and intellectual disability.