Cystic fibrosis is a recessive hereditary disease. The parents of children who have cystic fibrosis each carry one normal CFTR gene and one mutated CFTR gene. Choose the numbers to finish the sentence. If both parents each carry one mutated CFTR gene,
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of their children will probably have cystic fibrosis,
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of their children will probably be carriers, and
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of their children will probably not have cystic fibrosis or carry the mutated gene.