Read the sentence.
ancient remains are making the normally flat land hilly.
what kind of complement is indicated by the bolded word?
object complement
predicate nominative
direct object
predicate adjective

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.  

that is true because that is something they fulfill for their work.