According to erving goffman, one of the reasons it is important to study subtle day-to-day interactions is because:

According to erving goffman, one of the reasons it is important to study subtle day-to-day interactions is because: we can learn a great deal about ourselves as human beings
From examining every day-to-day interaction, we will understand how people have different opinions and response about certain things and how to learn from those difference to improve ourselves.

The answer should be a.