I did research but I couldn't find the exact answer but those are some websites maybe they could help you. I am sorry I did my best to help.
https://www.healthline.com/health/sickle-cell-anemia#outlook
http://sickle.bwh.harvard.edu/scd_inheritance.html
I hope those 2 websites help
Answer: was to increase the population of wolves
Explanation: The reasoning behind introducing these gray wolves (Canis Lupus) to the Greater Yellowstone Ecosystem was to increase the population of wolves there since they were once scattered because of people killing these animals off with the assumption that they were predators and were viewed as dangerous animals.
C. Desert
A. The tilt of the Earth's axis as it circles the Sun.
It’s B why do I have to write 20 characters