Question: Under what condition can group regrouping containing groups from multiple Mission Critical (MC) systems take place, if the policy of the MC system allows a temporary group to include groups from other MC systems?
Option 1: The MC service server (controlling role) for the regrouped group is the MC service server (controlling role) for all MC service groups involved in the regrouping.
Option 2: All groups to be regrouped are in an emergency state and belong to the same MC system initially.
Option 3: The regrouping is initiated by a User Equipment (UE) that is part of all groups involved in the regrouping.
Option 4: The MC service server (controlling role) for the regrouped group is determined randomly among the MC service servers of the involved groups.
Explanation: This option is correct because, according to the rules for preventing routing issues and complexity related to group regrouping in multiple MC systems, one of the allowed conditions when the policy permits temporary groups to include groups from other MC systems is that the MC service server (controlling role) for the regrouped group must be the same as the MC service server (controlling role) for all MC service groups involved in the regrouping. This ensures unified control and minimizes potential conflicts or complexities arising from the regrouping across different MC systems.