According to two teams of paleontologists, recent fossil discoveries in Pakistan show that whales, porpoises, and dolphins are more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today includes cows, camels, pigs, and hippos--than to any other mammals.
(A) that whales, porpoises, and dolphins are more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today includes cows, camels, pigs, and hippos--than (B) that whales, porpoises, and dolphins are more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today include cows, camels, pigs, and hippos--as (C) whales, porpoises, and dolphins to be more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today include cows, camels, pigs, and hippos--than they are (D) whales, porpoises, and dolphins as being more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today includes cows, camels, pigs, and hippos--as they are (E) whales, porpoises, and dolphins as more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today include cows, camels, pigs, and hippos--than