Answer: It's "Display rules" that makes, a person from the U.S. tend to associate an open-smile with happiness, while a person from East Asia may tend to associate a closed-smile with happiness
Step-by-step explanation
Display rules can be defined as culture norms learnt from early life/childhood, that determines and guides how one should express themselves. This display rules gives room for a person from the United State to associate an open-smile with happiness, while a person from East Asia may tend to associate a closed-smile with happiness.