Which of these descriptions indicate that the writer's purpose is to persuade readers?

A. an instructional book describing rules on how to operate a particular laptop
B. a note written by a 13-year-old boy to his parents giving different reasons why they should increase his allowance
C. the short story “Legends of Sleepy Hollow,” in which a headless horseman haunts the local townsfolk of Sleepy Hollow
D. an essay about the different techniques used in regulating air and water pollution