A、Because human faces have complex features. B、Because human fingerprints provide unique information. C、Because people’s behavio

Faces, like fingerprints, are unique. Did you ever wonder how it is possible for us to recognize people? Even a skilled writer probably could not describe all the features that make one face different from another. Yet a very young child or even an animal, such as a pigeon can learn to recognize faces. We also tell people apart by how they behave, when we talk about someone’s personality, we mean the ways in which he or she acts, speaks, thinks and feels that make that individual different from others. Like the human face, human personality is very complex. But describing someone’s personality in words is somewhat easier than describing his face. If you were asked to describe what a "nice face" looked like, you probably would have a difficult time doing so. But if you were asked to describe a "nice person", you might begin to think about someone who was kind, considerate, friendly, warm, and so forth. There are many words to describe how a person thinks, feels and acts. There are nearly 18, 000 English words characterizing differences in people’s behavior. And many of us use this information as a basis for describing his personality. People have always tried to describe each other. Actors in early Greek drama wore masks to show the audience whether they played the main bad character or the hero’s role. In fact, the words "person" and "personality" come from the Latin persona, meaning "mask". Today most television and movie actors do not wear masks. But we can easily tell the "good guys" from the "bad guys" because the two types differ in appearance as well as in actions.