One of the problems teachers face in class is nonparticipant students. In a class wh...

One of the problems teachers face in class is nonparticipant students. In a class where several students refuse to take part in the assigned activities, the teacher might:

I– use eye contact and continue speaking.
II– interrupt with "Thanks for that" and continue speaking.
III– ignore them if they are not disturbing others.
IV– stop mid–sentence and stare until the students stop.
V– ask colleagues how the same students participate in their classes.

Which of the actions above are correct?