Answer: The ethical theory that Mark has displayed in this case is moral relativism.
Explanation:
When a person is morally judged it can be either a true or false statement depending on the opinion of each person's standpoint. There are groups of people called moral relativists who argue that some people try hard to set and follow moral principles but can't because they keep running up against formidable objectives everywhere. They believe that some are more privileged than others and therefore can't follow the morals of everyone else.
This type of moral relativism started in Greece in the 5th century and is still occurring in modern times.