Which of the following best defines an 'oxymoron'?

An oxymoron is best defined as a figure of speech that combines contradictory terms to create a nuanced meaning or effect. This literary device often involves two opposing or contrasting words placed together in a way that highlights their difference while enhancing the overall meaning. For example, phrases like "bittersweet" or "deafening silence" invite the reader to explore complex emotions or ideas rather than taking them literally.

The other definitions do not capture this specific combination of contradictory terms that characterizes an oxymoron. A self-affirming statement, a consistent narrative viewpoint, or a rhetorical question does not involve the juxtaposition of opposing concepts in the same way as an oxymoron does. Thus, focusing on the essence of contradiction within the language is what makes the chosen answer accurate.