Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to prepare a dog for air travel [title] Check to make sure your dog should be flying. [step] Not all dogs are considered safe to fly. In general, airlines do not recommend that puppies under 8 weeks, elderly dogs, or sick dogs fly either in-cabin or as cargo.

Ending1: You will need to make sure your dog is safe on international airlines, too. Do this in advance of boarding the flight. Ending2: Short-nosed dogs, such as bulldogs and pugs, are not good candidates for being checked as they run the risk of overheating. Do not risk your dog's health and safety by having it fly when it is not fit to do so. Ending3: If it is safe to fly with your dog, you should consider it your responsibility as a parent for the dog. [title] Make sure your dog is able to survive. Ending4: [substeps] Commercial carriers specify or are required to physically transport overweight dogs so they do not get injured. [title] Make sure other animals are to be safely allowed on long flights.

Answer format: ending1/ending2/ending3/ending4