The answer is:
The characteristics of editorials
The characteristics of news reports
How news reports and editorials are similar
How news reports and editorials are different
An essay is brief piece of writing on a particular subject. Essays typically contain an idea in the introduction, called thesis statement, which the writer develops and provides evidence for in the next paragraphs.
In Hiroshi's essay, he must compare news reports and editorials. As a consequence, it is proper to describe their characteritics first, and then compare their similarities and differences.