Narratives are always fictional pieces of writing.

Narrative writing must tell a story. Fiction is writing that is imagined and not based on real events. Nonfiction is based on real events and could be narrative writing. Characteristics of narrative writing include characters, plot, conflict, setting, and point of view.

Explanation:

martians or other types of aliens represent a unique fear as opposed to zombies. vampires and other types of monsters.   in most sci-fi stories, aliens come from other worlds and have different or more advanced technology.   abductions and experimentation on human bodies that involve these technologies, or the use of these technologies against human beings and the use of unknown "powers", are a type of fear that's different from that of other types of monsters.