Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to help your cat breathe easier [title] Watch out for nasal discharge. [step] Runny noses are common in cats. If your cat has some nasal discharge around her nose, it may be mucus or muco-purulent, which is mucus stained with pus.

Ending1: These sorts of mucus are often yellow or green in color. [substeps] Some cats with nasal allergies may have a clear, dripping discharge from their nostrils, but this can be difficult to spot if the cat regularly licks it away. Ending2: While you should have your cat's and other feline's noses looked at by a vet, for example, if it is visibly bloody or has nasal infection, you should rule out any other abnormality as a cause for concern. [substeps] See your vet if your cat's nose is crusty with a foul smell. Ending3: Because this often manifests as bloody mucus or outside mucus, it is a good idea to watch out for any such discharge, just in case you notice it at any time. [substeps] It's possible the cat doesn't like to continue her breathing, but you may want to have it run lightly. Ending4: If your cat has nasal discharge, take care not to drip any of the fluid from its nostrils onto your cat. If your cat has a runny nose, and does not seem to be breathing right, or if the mucus looks milky around her nose and remains there, it may be a sign of infection.

Answer format: ending1/ending2/ending3/ending4