When Josephine says, “I beg; open the door- you will make yourself ill,” (line 70), the narrator and the audience know something that Josephine does not now. This is “dramatic irony.” What do we know that Josephine does not?

The dramatic irony is that while the characters did not know the true reaction of Mrs. Mallard, the readers/ audience knows that she is celebrating her husband's death, for it meant freedom for her.

Explanation:

Kate Chopin's short story "The Story of an Hour" revolves around the character Mrs. Mallard and how she reacted to the news of her husband's death. Contrary to the other characters' beliefs, she had a different side of reaction which was abruptly stopped by the sudden turn of events at the end of the story.

When the news of the death of Mr. Mallard first arrived, Mrs. Mallard immediately went to a separate room. The others thought she's been crying her heart out and would be heartbroken. But contrary to that, Mrs. Mallard was instead 'celebrating' the broken chain of her husband's hand/ control over her. She was free to think and do whatever she wants, whispering to herself "Free! Body and soul free!" All the while, her sister Josephine was pleading with her to open the door or else she'll make herself sick with worry and grief.

The dramatic irony is that while the characters did not know the true reaction of Mrs. Mallard, the readers/ audience knows that she is celebrating her husband's death, for it meant freedom for her. The audience/ readers are privy to the situation while the other characters are not.  

the correct answer is: d