The answer is B.Round. A round character is a complex character that often undergoes change and character development. While round characters are often main characters, this is not always the case and therefore the answer cannot be A, C or D.
An author might chose a first person narrator, because the first person narrator has a first person view of whatever the story is talking about. So a first person narrator makes an author more reliable and makes the story more personal.
The theme of the story expressed in that action is the submission and lack of freedom of women in marriages in those times.
In Chopin's "<em>The Story of an Hour</em>", Louise Mallard feels free when knowing that her husband passed away because she felt imprisoned being married to him. Given the patriarchal society and the way women were seen in her times, she never could really live the way she wanted and had to submit to him.
