Rouse some of the most irresponsible elements (4)
I believe the answer is:
stir
'rouse' is the definition.
(I've seen this before)
'some of the most irresponsible elements' is the wordplay.
'some of' indicates a hidden word.
'STIR' is hidden within 'most irresponsible elements'.
(Other definitions for stir that I've seen before include "Excitement" , "Create revolutionary movement" , "jug" , "Whisk or make a move" , "Arouse; commotion" .)