Answer:
D. He would take an explanatory tone with readers to reveal the different categories of advertisements
Explanation:
Since the author is informing readers about the different types of advertisements, he will have to take an explanatory tone. This is because the some of the readers may not be vast in the field of advertising. Therefore, the author will have to explain certain concepts on advertisement in order for the readers to grasp the information.
Also, informing readers about the types of advertisements will entail explaining those types/categories of advertisements for readers to understand.
Therefore, option D is the correct answer.
