阅读下面三部分内容，从各小题所给的四个选项中选出能回答问题所提问题或完成所给句子的最佳答案。
People are different. So are friends. Some friends are patient and helpful while some friends are cheerful and caring. The following are some kinds of friends. You can read it and find out what kinds of friends you have. This will help you to improve your relationships with them and help you to find new friends.
Animal Friends
Many people keep animals as pets at home. It is right to say that animals are wonderful creatures (生物). They can be with you whenever you need them. Some people say they will feel lonely without their pets. Dogs are considered as people's best friends.
Internet Friends
The Internet has become a very important part of our lives. It is not only helpful for people to work, but also a good way to make friends. Internet friendship has become more and more popular recently. More and more people begin to make online friends. Online friends are those who know each other through the Internet. They can talk about everything with each other online. Making Internet friends is similar to making pen pals.
Pen Friends
Pen friends, also known as pen pals, are quite popular with people who like writing. Pen friendship is mainly developed by writing to each other. It was a popular way of making friends in different parts of the world before the Internet came into being. Mostly, pen friends aim to share different cultures with each other.
