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Question
Cystic fibrosis (CF) is caused by a recessive allele. A child has CF, even though neither of his parents has CF. This couple also has a child who does not have CF. What is the probability the unaffected child is heterozygous?
A) 2/3
B) 1/3
C) 1/2
D) 3/4
E) 1/4
Answer
This answer is hidden. It contains 1 characters.
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