Julia had a sibling who died because of a genetic disease as an infant. Before having children, she and her husband Tobias get genetic testing and counseling. They are unlucky.
For the GAA gene, Julia has one normal allele and one totally non-functional allele. Tobias has one normal allele and one totally non-functional allele.
What is the likelihood that an offspring will have Pompe disease?
A) 0%
B) 25%
C) 50%
D) 75%
E) 100%