The study of human behavior is called psychology.
The facial feedback theory is defined as the reading the expression of the person for his behavior.
No one wants to make someone unhappy by saying something. Therefore, everyone smiles at the situation they do not want to answer and don't want to make them feel hurt.
According to the facial feedback hypothesis, people's emotional experiences are influenced by their facial expressions. Smiling, for example, should make people feel happier, while frowning should make them feel sadder.
A smile and happy face represent a good response
Bad face represents bad response
Hence, everyone showed with a smiling face
For more information on psychology, refer to the link:
brainly.com/question/20293447
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