You will be given a definition of a task first, then some input of the task.
In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D".

[header] How to train a therapy dog [title] Socialize your dog with a variety of people. [step] For a dog to become a great therapy dog, it should have early and consistent socialization. It should be exposed to people in a wide variety of locations starting at an early age. <sep> (A) This will help it get used to the wide variety of people and places it will visit as a therapy dog. [substeps] Make sure your dog is meeting people of different sizes, ages, genders, and ethnicities. (B) If you have a dog as an adult, you may want to introduce it to people through a social network so it can gain social support and see lots of people. Keep this in mind as you decide if you want your dog to socialize with visitors. (C) In order to accommodate this, even a small dog can be trained to socialize with a variety of people. On one hand, with a physical degree of exposure, a dog can quickly familiarize itself with a wide variety of people. (D) [substeps] Choose someone in your home with whom to socialize your dog. Choose a family dog, a puppy, or another dog that you trust.
Output:
A