A karyotype shows that a child has Klinefelter syndrome (47,XXY). If the child is also color- blind (due to a recessive X- linked allele), despite his parents having normal color vision, in which parent and stage of meiosis did nondisjunction occur?
A) father in meiosis I B) mother in meiosis I or II C) mother in meiosis II D) father in meiosis II E) mother in meiosis I