Final answer:
The correct works-cited entry for an editorial with an unnamed author in MLA format should include 'Editorial' after the editorial's title, followed by the name of the newspaper, publication date, and the URL.
Step-by-step explanation:
To edit the works-cited entry for an editorial in a newspaper, following the MLA format, and ensuring that it is free of formatting errors, the correct citation should include the title, followed by the designation Editorial since the author's name is not provided. The name of the newspaper, the publication date, and a complete URL should also be included. Here is the corrected format:
"Mars Beckons."
Editorial
. The New York Times, 27 Nov. 2018, www.nytimes.com/11/27/opinion/mars-exploration.
Most of the given options do not follow the standard MLA formatting for an editorial source, which requires the word Editorial to be added after the title when there's no author's name listed.