June has type B blood and has a baby, Joey, with type AB blood. Her husband, Jim, has type O blood. June believes that there has been a mix-up at the hospital. She suspects that another couple, Ann and Al, who had a baby the same day, were allowed to take her son home. That baby Arnie has type O blood. Al and Ann both have type A blood. Which of the following is a correct statement about who is Joey's father?
A) Neither Jim nor Al could be Joey's father.
B) Jim could be Joey's father, but Al could not.
C) Either Jim or Al could be Joey's father.
D) Al could be Joey's father, but Jim could not.
E) Al is definitely Joey's father, but Jim could also.

Question

Quizplus · Accepted Answer

Jim, with type O blood, cannot be Joey's father because he can only pass on an O allele, and Joey has type AB blood. Al, with type A blood, could be Joey's father if he carries an A and a recessive O allele, allowing him to pass on the A allele to Joey.

June Has Type B Blood and Has a Baby, Joey