To mark a single answer for the document as reviewed in the table row, hover over the answer, expand the row, if required, and select the Mark as reviewed icon. To unmark the reviewed answer, select the Mark as not reviewed icon.

Alternatively, to mark multiple rows and columns as reviewed, slide the Select mode toggle to right to enable it. Select the rows and columns and then select Mark reviewed as shown in the following figure:

To unmark the reviewed answers in bulk, with the select mode enabled, select the rows and columns which you want to unmark and then select Unmark as shown in the following figure: