Answer:
The correct answers are the options 3 and 4:
To reprimand participants who dominate other participants
To reiterate the purpose of the discussion if it becomes vague
Step-by-step explanation:
To begin with, the case that a discussion must take place in group meeting then it will depend on the subject that it will be discussed but the most probable is that a leader must be needed in order to initiate the discussion in the cases where he would need to reprimand participants who dominate other participants and also when the purpose of the discussion becomes vague. Those two are the main cases in where a leader will need to initiate and to intervene in a group meeting discussion