Answer: D
Correct answer: the number of spelling errors
Word Count reports pages, words, characters with and without spaces, paragraphs and lines. It does not report spelling errors - that is the job of the spelling checker, which is a separate tool on the same Review tab. The running word count appears in the status bar at the bottom of the window, and the full dialogue is opened by clicking it or from the Review tab. A detail worth knowing: selecting text before opening it counts only the selection, which is how a single section is measured. The dialogue also has a checkbox for Include textboxes, footnotes and endnotes, which is off by default - so a document with substantial footnotes will report a lower count than expected until it is ticked. The two character counts differ by exactly the number of spaces, and publishers and examinations use one or the other, so it is worth checking which is meant.