Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to treat heart disease in german shepherds [title] Look for a cough. [step] The most common sign of heart disease in a german shepherd is a cough. This usually occurs at night when the animal is resting.

Ending1: Additionally, it can occur whenever the dog is outside. If your german shepherd has a strong cough, this is one to look for. Ending2: However, since dogs sometimes have these symptoms, it is very rare for their cough to become more serious. [substeps] If the dog eats solid food, then his cough may be more serious. Ending3: At this stage, the dog might cough more than usual because the dog is recovering from an anxiety attack. The cough itself is not quite visible in a german shepherd. Ending4: Fluid buildup in your dog's lungs may trigger a series of coughing fits. If your dog coughs for more than three days, you should take them to the vet.

Answer format: ending1/ending2/ending3/ending4