根据短文理解，从A、B、C、D四个选项中选择最佳答案填空。
Farley worked for the Canadian government. One day. he was 1 to learn more about wolves(狼). Do wolves kill lots of caribou(北美驯鹿)? Do they kill people?
They gave him lots of food and clothes and guns. Then they put him on a plane and took him to 2. The plane put him down and went away. There were no houses or people in this place, but there were lots of animals and lots of wolves.
People tell terrible stories about wolves. They say wolves like to kill and eat people. Farley remembered these stories，and he was 3. He had his gun with him 4.
Then one day, he saw a group of wolves. There was a mother wolf with four baby wolves. A father wolf and another young wolf lived with them.
Farley watched these wolves every day. The mother was a very 5 mother. She gave milk to her babies. She gave them lessons about life. They learned how to 6 food. The father wolf got food for the mother. The young wolf 7 the children. They were a nice, happy family-a wolf family. Farley did not need his 8 anymore. In a short time, he got on well with the wolf family. Farley watched them for five months. He learned many new things about wolves. He learned that many stories about wolves were 9. Wolves do not eat people, and they do not eat many large animals. And he also learned bad things about men. It was men who killed many caribou and wolves.
Later, Farley wrote a book about wolves. He wanted people to 10 them and not to kill them.