How does the allele that causes sickle cell disease also confer a benefit to humans?
A. Mosquitos that bite people with sickle cell disease also contract the disease and die.
B. People with both copies of the sickle cell allele have sickle cell disease but are resistant to typhoid.
C. People with only a single copy of the sickle cell allele do not have sickle cell disease and are also resistant to the parasite that causes
malaria.
D. People with the sickle cell allele have more offspring on average.