To be really honest, I think its a matter of opinion on which sentence is the strongest conclusion. To me, I think choice C is the best answer because it paints the contrast between the dog's wild instincts versus loyalty. I guess the conclusion should also mention that despite the abuse, Buck still learned to trust a human (even though one could easily understand why the dog would never trust a human after the abuse), so it shows just how powerful loyalty can be.
They have Roman origin, they all have a specific meaning which is closely connected to their character, ex: Octavia is the feminine of Octavius, the family name of the man who became Octavian and then Augustus, first ’emperor’ of Rome.
