Answer: B) a final accomplishment or presentation before retirement.
Step-by-step explanation: the denotation of a word is its literal meaning, the definition that we can find in a dictionary, a word can have several denotations (or definitions). In the given sentence we can see the use of the term "his swan song" when referring to a soldier who will be addressing his soldiers. "Swansong" is a term which definition is "the final performance or activity of a person's career," so the correct answer is option B.