The Comments pane allows you to keep track of comments that have been added to PDF documents. The pane displays a list containing each comment, along with its type, reviewer name, time stamp, any text feedback, as well as any replies.
To sort comments:
Click the Comments icon in the side bar to open the Comment pane
In the Comments pane, click Sort By, and select a method to sort the comments, such as sort by Type, or sort by Author as some examples