When a cat is angry, it will growl and lower its body to the ground in an aggressive posture. In this situation, it is best for the owner not to touch the cat to avoid being attacked. 
Cats will growl when they feel violated or unhappy. For example, to warn another cat not to approach, a cat will make this low growling sound. If the other cat persists, the cat will start hissing at it.
The cat is growling. It's best to keep your distance and not provoke it. If you really anger it, it will definitely scratch you.
