Step 1 : Introduction to the question "What do elephants, rhinos, hippos and sloths have in common?"
...Elephants, rhinos, hippos and sloths are all mammals who give milk to their babies when they're first born. They all have backbones, are hairy and produce their own body heat. This means these mammals spend more time with their babies. Because it takes more time they also share another trait: they can't jump. There are actually three types of mammals: eutheria (placental mammals), marsupials (also called metatheria) and monotreness. Source: Reference.com
