Please choose the correct ending to complete the given sentence: Food and Entertaining: [header] How to know if a senior dog is right for your family [title] Realize that most senior dogs are trained. [step] Puppies are adorable creatures that are easy to love, but housebreaking a puppy can be a frustrating and tedious process. A prime benefit of bringing a senior dog into your home is that, in most instances, the housebreaking has been done for you.

Ending1: [substeps] There are no classes or levels of training. You only have to spend time with your senior dog first. Ending2: [substeps] Take your child to work or go for a walk with you so your aging dog is not left alone, especially when the house gets busy. Be mindful that most senior dogs will only be addressed if you leash-train them properly. Ending3: However, you should still be prepared to spend at least some time training your senior dog if you decide to get one. [substeps] Senior dogs are typically already potty trained. Ending4: In addition, a senior dog will not be easily replaced, unless its owner does not plan to spend time with it as a young adult. [title] Anticipate your dog's needs.

Answer format: ending1/ending2/ending3/ending4