The correct answer is diction.
Diction refers to the choice of words and phrases an author uses when writing. The diction used in a text or story tells us about the tone or attitude of the writer. Diction can be formal, informal, serious, playful, and so on. An example of formal diction would be: "Kindly revert back at the earliest possible convenience." Whereas, informal/playful diction would be: "I can't wait for your reply!"
it's D. Formal and Scholarly
