Q. People who inherit the sickle cell anemia gene from only one parent seem to be resistant to malaria, an evolutionary advantage that may explain why a genetic condition so debilitating to many individuals has survived in the human population.
(A) seem to be resistant to malaria,
(B) seemingly are resistant to malaria,
(C) seem to be resistant to malaria and have---
(D) seemingly are resistant to malaria and to have
(E) are, it seems, resistant to malaria, and they have

I chose [spoiler](C)[/spoiler]. OA is [spoiler](A)[/spoiler]. Any explanation?

Thanks,
Rohit.