For each of the following questions, choose the single best answer.

1. A man is diagnosed with a Glucose 6-phosphate deficiency subsequent to taking primaquine for malaria due to Plasmodium vivax. Which of the following pedigrees best illustrates the inheritance pattern of this trait?
   
   

   1.   ?    Pedigree A
   2.   ?    Pedigree B
   3.   ?    Pedigree C
   4.   ?    Pedigree D
   5.   ?    Pedigree E

2. A man who is affected with phenylketonuria marries a woman who is heterozygous at that locus. What is the probability that their first child will have phenylketonuria?

   1.   ?    1/8
   2.   ?    1/4
   3.   ?    1/2
   4.   ?    3/4
   5.   ?    1

3. An infant presents with failure to thrive, chronic airway infections, fatty stools, and elevated sweat chloride levels. Which of the following pedigrees best illustrates the inheritance pattern of this disease?
   
   

   1.   ?    Pedigree A
   2.   ?    Pedigree B
   3.   ?    Pedigree C
   4.   ?    Pedigree D
   5.   ?    Pedigree E

4. A young woman has long, slender limbs, arachnodactyly, myopia, and a superior dislocation of a lens. Her father and uncle both died from aortic dissection. Which of the following pedigrees best illustrates the inheritance pattern of this disease?
   
   

   1.   ?    Pedigree A
   2.   ?    Pedigree B
   3.   ?    Pedigree C
   4.   ?    Pedigree D
   5.   ?    Pedigree E

5. If the penetrance for familial polydactyly is 80%, what the probability that a woman with familial polydactyly will have a normal child?

   1.   ?    2/5
   2.   ?    1/2
   3.   ?    3/5
   4.   ?    3/4
   5.   ?    9/10