It isn't true it comes to a moral conclusion (5)
I believe the answer is:
fable
This might be a double definition.
'it isn't true it' is the first definition.
The definition suggests a singular noun which matches the answer.
'a moral conclusion' is the second definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'comes to' is the link.
Can you help me to learn more?
(Other definitions for fable that I've seen before include "Short moral story" , "there may be a moral to it" , "Aesop's story?" , "Old wives' tale" , "Myth, legend" .)