Answer:
Let ‘Xᶜ’ be the recessive allele for colour blindness and ‘X’ be the normal (dominant) allele.
Since Abby's father was colour blind, Abby must be a carrier for the same.
Which means Abby's genotype would be ‘XXᶜ’.
Now, Ryan is not colourblind which means his genotype would be ‘XY’.
Now, talking about their daughter, she would inherit a normal ‘X’ from Ryan and either ‘X’ or ‘Xᶜ’ from Abby.
Which means she wouldn't be colourblind but she might be a carrier of the disorder.
XXᶜ × XY
⬇️ ⬇️
X, Xᶜ X
↘️ ↙️
XX , XXᶜ
Their daughter will have either XX genotype or XXᶜ genotype.
And her chances of being colourblind thus, becomes zero.