Maurice is conducting a study on customer satisfaction for a firm. The study includes a survey that asks respondents to rate the firm on a scale of $1$ to $10$ across $20$ different criteria. During the coding process, Maurice notices that some respondents have provided the same value for each of the criteria. These respondents are most likely to be considered

curbstoners.

sort cases.

engaging presenters.

outliers.

straight$-$liners.