When answering this question, you can discuss the social and psychological effects of smiling. Smiling is often seen as a universal sign of friendliness and approachability, making people appear more open, positive, and easy to get along with. You can mention that people who smile frequently tend to create a warm and welcoming atmosphere, which helps build trust and good relationships with others. However, you might also point out that while smiling can be a sign of friendliness, it does not always reflect a person's true character, as some people may smile out of politeness or habit rather than genuine friendliness.