As per the Instructor Role update version 3.3.0, Instructors now also have the ability to view and reply to comments posted by students on their courses, lessons, topics and quizzes.
There is a new menu in the Instructor Dashboard for Comments where the instructor can view all the comments on their course content.
They can Approve valid comments, Spam or Trash invalid ones, Edit and Reply to them directly from the Instructor Dashboard itself.