Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to introduce new pets [title] Research the realistic compatibility of your new pet being housed with your old pets, preferably before you select your new pet. [step] In addition to predator/prey relationships, some animals can be very territorial and aggressive towards members of their own species. Learn what you can beforehand and you'll have a better idea of how much peaceful interaction you can expect your animals to have.

Ending1: [substeps] Remember that this search can take several days, weeks or months, so do not wait any longer than that. [title] Consider adopting more aggressive animals such as pythons. Ending2: Consider these things before choosing a new pet : [substeps] You may want to keep your new pet's identity secret. Keep the initial introduction and interactions at a comfortable distance if you do not want to harm your new pet. Ending3: It may also help to consider if your new dog or cat will enjoy being with you. [title] Take your time and choose the best companion. Ending4: [title] Consider the personality of your current pet or pets. [step] Think about how your pet acts around you and around other animals.

Answer format: ending1/ending2/ending3/ending4