Answer:
I'm pretty sure its B. voluntary-response bias
Answer:
how does it work, how does motor function relate to the brain, what are the different sections of the brain.
Explanation:
I think D from what I remember in Biology when I was in freshman
Sickle cell anemia is persistent in the tropics because those with sickle cell anemia cant contract the malaria virus because of the shape of their blood cells, and this is advantageous in the tropics where there are more malaria cases. So those with sickle cell anemia live to pass on their genes.