A woman with type O blood is expecting a child. Her husband is type A. Both the woman's father and her husband's father had type B blood. What is the probability that the child will have type O blood?

• A. 100%
• B. 75%
• C. 25%
• D. 0%
• E. 50%

Answer: (E)

Verified step by step guidance

1. Understand the inheritance of blood types: Blood type is determined by alleles A, B, and O. Type O is recessive, meaning a person must inherit two O alleles to have type O blood.
2. Identify the genotype of the woman: Since she has type O blood, her genotype must be OO.
3. Determine the possible genotypes of the husband: He has type A blood, which means his genotype could be AA or AO. Since his father had type B blood, he must have inherited an O allele from his father, making his genotype AO.
4. Set up a Punnett square: Use the woman's genotype (OO) and the husband's genotype (AO) to create a Punnett square. This will help visualize the possible genetic combinations for their child.
5. Analyze the Punnett square: The Punnett square will show that there is a 50% chance of the child inheriting OO (type O blood) and a 50% chance of inheriting AO (type A blood).