For an animal to be considered kosher, it is essential that it has both a split hoof and chews its cud. This requirement comes from the dietary laws outlined in the Torah, specifically in the book of Leviticus, which detail the characteristics that land animals must possess to be deemed kosher.
Animals like cows and sheep meet this criterion as they have split hooves and are ruminants, meaning they chew their cud. This classification not only reflects the dietary laws of kashrut but also emphasizes the importance of specific traits in animals that are acceptable for consumption in Jewish dietary practices.
The other choices, while they may relate to various aspects of animal classification, do not fulfill the kosher status requirements set forth in religious texts. For example, being a carnivore or being domesticated doesn't determine kosher status, nor does it simply suffice for an animal to be a mammal; the iconic traits of split hooves and cud-chewing are non-negotiable for an animal to be recognized as kosher.