Think of sociology as socially and you’ll be set. then the studies of relationships between groups or individuals is obviously psychology
There were of course other factors. While early humans did hunt them a lot due to the profits which they received from it (A lot of food, bones they could use for homes, fur they could use for clothing, etc.), there were also other factors such as less food for them which made them less mobile through different geographical regions, etc. (and therefore more susceptible to being hunted) that had played a part in their extinction.
The answer is B i am positive
In the novel, the ghost shows him all of London celebrating Christmas, then leads him to Fred and the Cratchit family.