The correct answer is the first option. Edgar Allan Poe uses fear to create a single effect in “The Fall of the House of Usher”? The single effect is a paradigm created by Edgar Allan Poe that signifies that a story must produce one specific and consistent effect in the reader. The fear as a single effect is unified in this story through carefully chosen words when describing the characters, settings, actions and writing dialogs. For example, throughout the story, reader can sense the depression and fear surrounding every element in the house of Usher.