Answer:
A plot is an important element of a short story because with out the plot, there would be no sotry itself, think of it as writing a script, the plot is like the guide to where the story is going
Example: 'snow white goes to a house of seven dawrfs, she currently lives in the house when suddenly she hears a knock, she opens the door to see a hag with an apple, she eats the apple ad gets poisoned, the dawrfs see this and are mourning her death, then a prince comes and saves her life"
That is the plot of snow white, the topic, the theme, I'm not good at explaining hope you understand though.