The correct answer is "Ethos".
"Ethos" is a Greek word that means "character". It is also used to make reference to beliefs or ideas that characterize a group of people. This term is often used to describe the persuasive technique of being able to reach someone's behavior or morals and influence them in order to obtain the desired result.
In this case, Laurel is trying to convince them that she has a strong sense of responsibility, as she has worked as a baby sitter before despite having the option to go out with her friends.