Cystic fibrosis is a recessive gene disorder. The pedigree chart for a family known to have cystic fibrosis is shown below. What percentage of the offspring either are carriers or have observable disease?

25%
50%
75%
100%

When half of the shape is black it means the person is a carrier. When the whole shape is black this means the person has the disorder.

d.100%

Hope this helps

it is either c or d and i know for sure it is not a or b

thinking it would be d not too sure but i think it's right