Which statement about cystic fibrosis is true?(1 point)
A) Cystic fibrosis affects a person's ability to make normal red blood cells.
B) Cystic fibrosis is caused by a deletion of one codon in the DNA molecule.
C) Cystic fibrosis is caused by a mutation in which a dominant allele replaces a recessive allele.
D) Carriers have an advantage over people who do not have the cystic fibrosis mutation.