Which statement best defines a theme in a short story?

The first time I ever saw Peter was in St. Louis in 1892, and I had come down from Chicago to work on the St. Louis Globe-Democrat. He was a part of the art department force of that paper. At that time—and he never seemed to change later even so much as a hair's worth—he was short, stocky and yet quick and even erky in his manner, with a bushy, vagabond-like "get-up" of hair and beard, most swiftly and astonishingly disposed of at times only to be regrown at others, and always, and intentionally, I am sure, most amusing to contemplate. In addition to all this, he had an air of well-being, force, and alertness. It belied the other surface characteristics as anything more than a genial pose or bit of idle cheerfulness.

Plainly, he took himself seriously and yet lightly, usually with an air of suppressed joy, as though saying, "This whole business of living is a great joke." He always wore good and yet exceedingly mussy clothes, at times bespattered with ink or, worse yet, even soup—an amazing grotesquery that was the dismay of all who knew him, friends and relatives especially.
A.
A theme helps build tension between the characters in a story.
B.
A theme is the central message, moral, or lesson conveyed using characters, setting, and plot.
C.
A theme is the use of an object to represent a larger idea.
D.
A theme is the topic of a story, which the author develops through a particular tone and mood.
E.
A theme helps reveal the order in which events occur in a story.