What indicates that the woman was unaware of her invitation to the wedding?

The statement "I haven't" indicates that the woman was unaware of her invitation to the wedding because it communicates that she has not received the invitation or has not been made aware of it. This response suggests a lack of prior knowledge about the event, which is why she uses the present perfect tense. This tense often implies that something has not happened up to the present moment, reinforcing her unawareness of being invited. The other options do not convey this sense of lack of awareness about the invitation. Each of those alternatives indicates a different nuance of meaning that does not relate to the concept of being unaware of receiving an invitation.