Alice's study examined the benefits of early morning exercise on young children's attention during circle time. She had two groups of students, one who came to circle time first and then had recess and a second group that had recess before circle time. She is comparing the groups' attention based upon a frequency of off-task behaviors by group at circle. The likely descriptive statistic for Alice's dependent variable is
◦ the range of off-task behavior by group.
◦ the median off-task behavior by group.
◦ the mode off-task behavior by group.
◦ the mean off-task behavior by group.