Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to diagnose canine cancer [title] Look for lumps on the skin. [step] The most important thing you can do is to be alert for changes in your dog. This includes paying attention to lumps, like watching for the growth of a new lump on the skin, the enlargement of an existing lump, and a change from a lump not bothering the dog to becoming angry-looking or itchy.

Ending1: [title] Take your dog to the vet for several days. [step] The vet will discuss treatment options with you and schedule a consultation. Ending2: [substeps] Lumps on the skin can disrupt your dog's immune system, preventing it from eating healthy meat properly and inappropriately. [title] Detect any reddish red bumps on the dog's skin. Ending3: [title] Watch for unexplained weight loss. [step] Another common symptom of canine cancer is weight loss. Ending4: [title] Take a look at the dog's eyes. [step] Those classic beagle dog eyes are usually red, swollen, and inflamed.

Answer format: ending1/ending2/ending3/ending4