Guide Dogs Guide Dogs Are Service Animals That Are Specially Trained to Trained

Guide dogs
Guide dogs are service animals that are specially trained to help visually impaired people. Most guide dogs are Labrador Retrievers, Golden Retrievers, or German Shepherds, breeds known for their intelligence, gentleness, and friendliness. Puppies that might become guide dogs are monitored from a very young age by trainers. Puppies that demonstrate a good temperament and willingness to learn begin their training at about 16 months of age.
Puppies that have been selected for training live with their trainer's family for about a year. Trainers teach the puppies to walk in straight lines, avoid obstacles, and stop at curbs. The dog learns how to focus on the owner instead of distractions, such as food, toys, or other animals. Guide dogs learn how to obey their owners, but also when to refuse their owner's commands when it might lead to danger, such as crossing a busy street.
When the dog is full-grown, the trainer brings it in for a final assessment. If the dog passes the test, it is placed with a visually impaired person in need of a service animal. If the dog fails the assessment, however, it often remains as a pet with the trainer's family. Although trainers might be sad to part with the dog that they have bonded with, they know that their former charge has become an invaluable resource for someone in need.
What is the best summary for this passage?

A) Becoming a guide dog is a difficult and tiresome process, but it is well worth it because guide dogs are able to help visually impaired people.
B) Guide dogs usually do not pass their assessment during the first try, and often remain with the trainer's family.
C) The journey to becoming a guide dog contains a training period as well as an assessment, which, if successful, benefits visually impaired people.
D) Trainers have a difficult job when training a guide dog, especially because it comes with emotional trials and tribulations.