Solution

Colourblindness is a X-linked recessive disorder. One copy of the affected gene in males in each cell is sufficient to cause the disorder (X$$^{c}$$Y). Females with two copies of the affected gene show the disorder (X$$^{c}$$X$$^{c}$$). Females heterozygous (X$$^{c}$$X) for this trait be normal but serve as a carrier of the disease. For a daughter to be affected, it should receive one copy of "X$$^{c}$$" allele from both parents which means that father should be affected and mother should be carrier or affected. This makes options A, B and C wrong because either mother or father is normal in those options. A carrier mother and colourblind father can give birth to a colourblind daughter because both parents carry one copy of affected allele. Correct option is "D".