Why is "The Story of an Hour" ironic?

a. Mrs. Mallard feels herself trapped in an unhappy marriage.

b. The characters and the events are exaggerated.

c. The plot turns out differently than expected.

d. The reader knows what is going to happen before the characters.

Irony is when something unexpected happens, usually the complete opposite. In "The Story of an Hour" Mrs. Mallard is told her husband is dead, and she becomes excited at the idea of being able to live just for herself. At the end of the story her husband walks in the door and she dies of presumably a heart attack at the sight of her freedom being stripped away. The answer is C because the reader not only does not expect the ending.