Explanation
Correct answer: D.
Choice D is the best answer because it best describes the overall structure of the text. The first part of the text presents the favorable opinions that others hold of Mr. Ely: the laity of Milby regard him as having "remarkable powers and learning" and assume that he also impresses people in London, while his fellow clergy see him as "a discreet and agreeable fellow." The text then goes on to describe Mr. Ely’s behaviors that enable him to cultivate and preserve his positive reputation. The text conveys that he avoids confrontations, abstaining from "warm discussion[s]" (that is, heated or contentious ones); that he avoids offending anyone by "rarely [saying] what he thought himself" and by refraining from openly ridiculing anyone; and that he doesn’t give anyone any reason to ridicule or belittle his own character ("he never gave any one an opportunity of laughing at him"). In other words, these are all behaviors that suggest that Mr. Ely avoids doing anything that might make people dislike him or think poorly of him. Thus, the text begins by presenting the favorable view that people have of Mr. Ely and then describes the behaviors that enable him to maintain that favorable view.
Why the other choices are wrong
Choice A
Choice A is incorrect because the text doesn’t describe any events that caused people’s regard for Mr. Ely to diminish. Instead, the text explains that the people of Milby hold him in high regard and describes behaviors that suggest how he cultivates that regard.
Choice B
Choice B is incorrect because the text doesn’t suggest that Mr. Ely’s neighbors are more naïve than Londoners are or that they’ve been misled. Although the text suggests that Mr. Ely is very guarded in his outward behavior and conceals from people when he may be internally mocking them, which might suggest that people know him less well than they think they do, there’s nothing in the text to suggest that Londoners are less naïve and therefore less easily misled than Mr. Ely’s neighbors are. The text states that the people of Milby believe Mr. Ely to be "remarkable" and that they assume that people in London must find him so, too; it doesn’t say anything about what Londoners actually think of him.
Choice C
Choice C is incorrect. While the text discusses Mr. Ely’s public conduct at length, describing the ways in which he carefully cultivates an agreeable public persona, the text doesn’t discuss how Mr. Ely behaves in private at all; it therefore wouldn’t be accurate to say that the text begins by emphasizing a discrepancy between his public and private conduct. Furthermore, although the text concludes with examples illustrating that Mr. Ely typically doesn’t share his true thoughts, indicating that he may be hiding aspects of his true personality when in public, and although the text as a whole conveys the idea that Mr. Ely benefits from this behavior, which might hint at his motives for doing so, the text doesn’t conclude by alluding to those motives. Instead, the text merely concludes with a description of the behaviors he engages in to win his neighbors’ and colleagues’ approval.