Question

What must be true of a person with cystic fibrosis?

a. At least one parent was a carrier for cystic fibrosis.
b. The mother was a carrier for cystic fibrosis.
c. One of the parents had the condition cystic fibrosis.
d. Both parents had at least one allele for cystic fibrosis.

Answer 1

D. here is a picture to help you-

hope this helps

Answer 2

The answer is D. For future use you can use a punnet square to help you if need.