the pedigree below tracks duchenne muscular dystrophy (dmd) through several generations. Dmd is an x-linked recessive trait

Answer 1

Generation 1
Grandma (Carrier) x Grandpa (Normal)
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Generation 2
Daughter (Carrier) x Son-in-law (Normal)
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Grandson (Normal) Granddaughter (Carrier)
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Generation 3
Great-grandson (Affected)