Final answer:
The rhetorical devices present in Iago's lines are irony and rhetorical questions, serving to challenge beliefs and provoke thought.
Step-by-step explanation:
The rhetorical devices present in the lines by Iago in Act III, Scene 3 of Othello are irony and rhetorical questions. The purpose of these devices is to create a sense of doubt and to challenge the beliefs and motives of the other characters. Iago uses irony to highlight the hypocrisy and double standards of society, while the rhetorical questions are used to provoke thought and make the audience question their own assumptions.