Color blindness is typically an X-linked recessive trait, meaning it is carried on the X chromosome. A woman has two X chromosomes (XX), while a man has one X chromosome and one Y chromosome (XY).
If the woman passes on a color-blindness allele (which we can represent as "c"), the scenario is as follows:
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The girl (XX) could either inherit the normal X chromosome (X) or the color-blindness X chromosome (Xc) from her mother, and she would inherit a normal X from her father. She would only be color-blind if she inherits the color-blind X chromosome from both parents (thus, XcXc), which is not possible in this case since her father does not carry the color-blindness gene. Therefore, the girl can be a carrier (XcX) but not color-blind.
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The boy (XY) inherits his X chromosome from his mother and his Y chromosome from his father. Thus, if he inherits the color-blind X chromosome (Xc) from his mother, he will be color-blind (XcY).
Given this genetic relationship, the boy is more likely to be color-blind if he inherits the color-blind allele from his mother.
So the correct response is: the boy is more likely to be color-blind from birth.