Setup: A course with at least one teacher and one student enrolled. In the course, create an assignment of type "Upload a single file" (with default settings). Log in as the student, and open the assignment. Click "upload files", add a file to the list, click "Save changes". Log in as the teacher, and open the assignment. Click "View 1 submitted assignments". Click "Grade" next to the student's submission. In "Response files" section, click "Add", and add one file. Click "Save changes". Log in as the student, and open the assignment. TO VERIFY: The student now sees the response file uploaded by the teacher, below the heading "Submission feedback".