Answer:
Social
Step-by-step explanation:
Significant deviation from commonly accepted pattern of thought, emotion or behaviour is called abnormality. It is the absence of illness and the state of state of well being. Abnormal behaviours are self defeating, disturbing and self defeating. Deviance, Dysfunction, distress and danger are the four D's of abnormal behaviour.
Thomas's behaviour is abnormal because he was a successful person and as per social norms every one wants to become successful. But he left what ever he had achieved and joined the monks. It can be considered an abnormal behaviour from social perspective but is may not be so if questioned from personal perspective.