Hello!
Although I twisted my neck reading that, hehe..
Let me explain,
Climax is a turning point of a narrative work<span> is its point of highest tension and drama, or it is the time when the action starts during which the solution is given.
</span>Exposition in literature is a literary term that refers to the part of a story that sets the stage for the drama to follow: it introduces the theme<span>, setting, characters, and circumstances at the story’s beginnings.
</span>Falling action<span> is the part of a literary plot that occurs after the climax has been reached and the conflict has been resolved.
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Conflict<span> is a </span>literary<span> element that involves a struggle between two opposing forces usually a protagonist and an antagonist.
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What do you think it is?
(I'll provide the answer but I want you to think for yourself for a moment)
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When you enumerate you need to put comas between all the items except the ones which are connected by "and" : as A is not correct as it does not have comas, and B is incorrect as it has comas where "and" is.
now, in a way both C and D are correct, but C is the usual accepted version, and D is an example of "Oxford coma" (where the coma is optional, to remain on the safe side, choose C).
