Which of the following is not true of the theme of a work of literature, such as a novel, short story, or play?
a. a good theme is universal.
b. it's the central idea or concept in a piece of writing.
c. it can be stated in a word or two.
d. it is a generalization.

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.  

what your measuring and how much your measuring