Which is not an example of irony in "The Story of an Hour" by Kate Chopin?

The doctors diagnose the death of Mrs. Mallard as "joy that kills."

We are looking for NON examples of Irony.

Answer: Mrs. Mallard bursts out weeping when she hears the news of her husbands death.

Explanation: The multiple choice answers I have are

A. The doctors diagnose the death of Mrs. Mallard as "joy that kills" (which is an example of dramatic irony as she actually was not joyful at all upon seeing her husband)

B. When she sees her husband, Mrs. Mallard dies of heart failure (Also irony)

C. Mrs. Mallard bursts out weeping when she hears the news of her husbands death. (this is the most non ironic answer.)

D. In the midst of Mrs. Mallards grief, she sees and hears the signs of spring (quite ironic that someone who is grieving would hear signs of spring)