Answer:
Appreciating Mark's work in the presence of his classmates.
Step-by-step explanation:
The first one is not a positive reinforcement lol- that would make him embarrassed and he would most likely start to blame himself and lose motivation making the situation more difficult..
Third one- detaining him wont do anything for that situation unless hes talking about ways to help him improve on getting in work on in time.
The last one will make him feel good about himself and will make him want to do better including enhancing his slight mistakes- such as being late. Seems like the only reasonable answer. :)