Few teachers have been spared the problem of an obstreperous pupil in the class.

Answer: Option B

sullen : bad-tempered and sulky.
unruly : disorderly and disruptive and not amenable to discipline or control.
lazy : unwilling to work or use energy.
awkward : causing difficulty; hard to do or deal with.
obstreperous : noisy and difficult to control.


Synonym of obstreperous is unruly