The answer is d. all of the above are true.
Procrastination is a common behavior found in students, wherein they put off studying or important school-related tasks for later occasions. Procrastination is harmful because it can lead to high levels of stress, which in turn can affect health, sleep and lead to poor eating habits. Procrastinators also receive lower grades generally since they do not end up having sufficient time to prepare for exams or complete their assignments.
