A Professor has posted the grades of all students on the wall outside the classroom.

Which of the options below is an appropriate way in which the grades could be posted to remain in compliance with FERPA?

Grades are posted using the student$$s ID number.

Grades are posted using a random number known only to the student and instructor in that particular course.

Grades are posted with the last four digits of each student$$s SSN as the identifier.

Grades are posted using a combination of the students institutional ID and social security number.