A. Horse
The same way other mammals (like humans) do.
You could be correct there. Africa has a huge variety of antelopes and horse related mammals and many others with hooves.
Mammals are not closely related to reptiles
Equus
Horses are mammals.
Yes
no some mammals like a horse have hooves.
No. The hippopotamus is not very closely related to horses, although of course both species are mammals. The hippopotamus is a type of even-toed ungulate and is thus more closely related to camels, cows, and pigs, than it is to horses. Horses technically do not have toes, but the hoof of a horse is equivalent to a highly developed toenail of a single toe, making horses a kind of odd toed ungulate.
Dolphins eat octopus, squid, small fish and shrimp.
Mammals are distantly related to birds. Oddly, if you look at an evolutionary tree, birds are actually more closely related to reptiles than they are to mammals.
They are both mammals.