Thomas Suffers from a Sex-Linked Blood-Clotting Disorder Called Hemophilia That

Multiple Choice

Thomas suffers from a sex-linked blood-clotting disorder called hemophilia that is transmitted by a recessive gene.Neither his mother nor his father has ever shown symptoms of this disease.What can we conclude about the genetic makeup of John's parents?

A) Both the mother and the father have the faulty gene.
B) The mother is a carrier for hemophilia, while the father does not have the gene.
C) The mother is homozygous for the faulty gene, while the father is heterozygous.
D) The father has the faulty gene, while the mother does not.