Question

In order for a child to inherit a recessive genetic disease like sickle cell anemia, healthy parents must both A. have the disease. B. be homozygous for the mutated gene that causes the disease. C. be carriers of the mutated gene that causes the disease. D. have other offspring that have the disease

Answer 1

C. 
A is incorrect because if they have the disease then they cannot be healthy.
B is incorrect because if the genetic disease is recessive then the cannot have the homozygous mutated gene because then it would mean that they are ill.
D is incorrect because having an offspring that is ill doesn't always guarantee that all the offspring will be ill. <span />