Read the passage below to answer the question:Hemophilia is a disorder in which blood fails to clot. Saad, a male hemophiliac, marries Sara, a normal woman and together they have four children, two boys (Ahmed and Ali) and two girls (Alia and Ayesha). None of the children display the symptoms of Hemophilia. Ahmed, Ali, Ayesha, and Ali all marry normal individuals and have children. None of Ahmeds or Ali's children, male or female, display symptoms of hemophilia, but the sons of Alia and Ayesha display symptoms of hemophilia while the daughters of Alia and Ayesha do not. Which of the following individuals are heterozygous for hemophilia:

Explanation

Hemophilia is an X-linked recessive disorder, meaning that males (XY) need only one affected X chromosome to express the disorder, while females (XX) need two affected X chromosomes to have the disease.Saad (hemophiliac male) has only one X chromosome, which carries the hemophilia mutation, and a Y chromosome.Sara (normal female) has two normal X chromosomes.Ahmed and Ali (sons of Saad and Sara) inherit their Y chromosome from Saad and a normal X chromosome from Sara, so they are unaffected.Alia and Ayesha (daughters of Saad and Sara) inherit one affected X chromosome from Saad and one normal X chromosome from Sara, making them carriers (heterozygous) for hemophilia.Since Alia and Ayesha are carriers, they do not show symptoms themselves but can pass the affected X chromosome to their sons. Their sons receive their Y chromosome from their fathers and have a 50% chance of inheriting the affected X chromosome from their mothers, leading to hemophilia.Thus, Alia and Ayesha are heterozygous for hemophilia.