What elements should an assertion contain?

The elements that an assertion should contain are topic, stance, and emotional appeal

Explanation:

An assertion is a strong statement a person makes about something they really believe in, that makes it very personal and emotional, since it commonly represents a belief that is not necessarily proofed to be real, in fact, in many cases there is no evidence to show whether the statement is true or false beyond the authors words.

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.  

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