Guide dogs   are a big help to blind people. A guide dog helps its owner cross the street and do many other things. But it is not easy to become a guide dog. Here's what a dog must do to get the job: 1. When the dog is very young, trainers watch the dog to make sure it is friendly and quiet. 2. For one year, the dog goes to live with a testing   family. The family teaches the dog some simple words, like "Sit!" and "Stay!" 3. Then the dog goes to school, where trainers teach the dog to lead a person. The dog must learn to _ cars and other dangers in the street or in the neighborhood. 4. The trainers take the dog into town to practice going into stores and banks. 5. If the dog has done well at school, it is ready to meet his blind owner. Now they will work as a team. You would probably find this passage in   _  .
a book about families a book of stories a book about working animals a book of cartoons