Research indicates that students who procrastinate: a. suffer significantly more stress as compared to non-procrastinators. b. develop more health problems as compared to non-procrastinators. c. tend to earn lower grades as compared to non-procrastinators. d. all of the above are true.

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. 

The  ancient egyptians  who  built the pyramids  may have been  able  to move massive stone blocks across the desert by wetting the sand in front of a contraption  built  to pull the heavy objects