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With the help of given pedigree, find out the probability for the birth of a child having no disease and being a carrier (has the disease mutation in one allele of the gene) in $F_{3}$ generation.
A
1/4
B
1/2
C
1/8
D
Zero
Explanation
Probability of a carrier female child ($X^C X$) from a carrier mother ($X^C X$) and normal father ($XY$) is 1/4.
Detailed Solution
The pedigree shows X-linked recessive inheritance. In $F_2$, the mother is a carrier female ($X^C X$) and the father is unaffected ($XY$). The offspring genotypes are: $X^C X$ (carrier female, 1/4), $XX$ (normal female, 1/4), $X^C Y$ (affected male, 1/4), $XY$ (normal male, 1/4). The probability of an unaffected child being a carrier is 1/4.