Tay Sachs Disease Is the Result of Abnormal Genes, Much

Tay Sachs disease is the result of abnormal genes, much like sickle cell, and both can be identified with genetic screening. As a result of screening programs, Tay Sachs is now very rare in North America, but sickle cell is not. What's different between these cases?

A) Tay Sachs is worse, so people pay more attention to positive results if they are screened.
B) The Tay Sachs screening program started with good education and cultural sensitivity toward participants so people are more willing to be tested.
C) The sickle cell screening program started with good education and cultural sensitivity but health insurance didn't cover the tests.
D) Sickle cell alleles are much more common to start with, so it's been more difficult to eradicate the disease.
E) Sickle cell disease doesn't show up until much later in life than Tay Sachs.