Exasperates
(Other definitions for riles that I've seen before include "Irritates, nettles" , "Annoys in American way" .)
'exasperates' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for irks that I've seen before include "Annoys, vexes" , "'Irritate, annoy (4)'" , "Galls" , "Annoys, irritates" .)
(Other definitions for angers that I've seen before include "annoys" , "Winds up" , "Irritates" , "Outrages" , "Maddens" .)