What is the mood of the story edgar allen poe

The mood of the story is a Dark Suspenseful mood, Hope this Helps :D

In most of his books the mood is set as dark, suspenseful, gloomy.

the following key ideas correctly express the key sentence.

restate key idea: most people can learn to swim in ten short lessons.

restate key idea: the majority of water-accident victims require mouth-to-mouth breathing.

restate key idea: an empty, tightly closed gallon jug will support a tired swimmer.  

restate key idea: first aid is to prevent accidents as well as assist in rescue.

explanation: the key idea needs to have the same topic as the key sentence (drowning and safety).

the answer to "what does the narrator realize by the end of the story" is b.