University of Maryland students were faced with a rather cruel dilemma at the hands of their social psychology professor, who set them a fiendish question designed to test their morals.
The question put to the American students, who had the opportunity to gain extra credit, read: Select whether you want 2 points or 6 points added onto your final paper grade.
"But there's a small catch: if more than 10% of the class selects 6 points, then no one gets any points."
Dr Dylan Selterman, the evil genius behind the question, told ABC he had been handing out the exercise since 2008, and almost without fail, more than 10% of the class chooses the six point option.
"Only one time did students stay under the threshold for the selfish option. I think that was a random fluke," he said.
Selterman says the question has been around for a long time, and was even given the exercise himself when he was a student. "When I was an undergrad in his class, I chose the lower point option and was very upset with my peers for choosing the higher point option!"
The task is aimed to teach students the way a group's action affects individuals, demonstrating how common resources get destroyed when they are available for everyone to use.
"In reality, if too many people overuse a common resource then everyone in the group suffers, not just the selfish ones," Selterman added. "This is what I want students to learn from the exercise. Their actions affect others, and vice versa."