The support activity carried out by Mark's team follow a workflow that has a workstage 'Compliance Confirmation' with a WIP limit of $5.$ What does this mean?

There should be a minimum of $5$ tasks under this workstage, at an instance of time

There should be exactly $5$ tasks under this workstage. at an instance of time

There can be a maximum of $5$ tasks under this workstage at an instance of time

There should be $5$ team members attending to the tasks present under this workstage