From the story Oedipus in line 109 in the literature book what is dramatically ironic about

Our first example of unconscious or dramatic irony can be seen in a discussion about Laios by Oedipus and Creon. Oedipus says about Laios: "I know: I learned of him from others: I never saw him." (pg. 862, lines 108-109). This passage constitutes unconscious irony as Oedipus believes that he is speaking the truth - that he never met Laios. Of course, the audience, armed with fore-knowledge, know that it is not. Oedipus not only has met Laios (his real father), he killed him at the crossroads "where three highways meet."