Final answer:
One unique aspect of Maria Irene Fornés's play Fefu and Her Friends is the use of site-specific theatre, where the audience is divided into groups and taken to different locations to view scenes.
Step-by-step explanation:
One unique aspect of Maria Irene Fornés's play Fefu and Her Friends is that during one part of the play, the audience is divided into four groups and taken to different locations to view scenes. This technique is known as site-specific theatre or immersive theatre, where the audience becomes an active participant in the performance by physically moving through the set and experiencing the scenes in different locations.