Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to stop a cat from biting or scratching during play [title] Recognize play aggression. [step] If your cat's ears flatten, its tail flickers and it stares at you, it may be exhibiting play aggression. However, it shouldn't look like your cat is in pain.

Ending1: If it takes attention off of you, then the behavior is either based on feeling threatened or for some reason because it wants to get attention. [substeps] If you can detect the behavior in your cat, give it a gentle warning. Ending2: There shouldn't be any growling or hissing sounds, which could indicate more serious forms of aggression due to physical pain or injury. [substeps] If your cat is exhibiting aggression and you don't know if it is play aggression or aggression due to a serious illness, you should get it checked out by a veterinarian. Ending3: [substeps] If you don't recognize play aggression, your cat may bite or scratch at you. This is most common if you see your cat bite someone, in which case you should immediately report it to your veterinarian or have the cat removed from play. Ending4: This means that the cat is playing, and shouldn't bite or scratch at you in an attempt to calm itself down. [substeps] Humans will generally be able to tell when a cat is in pain and may even pull its tail back in an effort to avoid oncoming aggression.

Answer format: ending1/ending2/ending3/ending4