Obsessed is most appropriate to describe a person whose mind and heart are concentrated on one idea to the exclusion of everything else.
I hope this helps you. ☺
You have to show us or tell us the story that goes with this.
When a story is written in third person point of view, it may cut off some of the personal feelings you might get if you were reading the story in first person, or even second person point of view. The thing is, first person is a lot more personal than third person. Third person is kind of like just telling you the story. (Although it is not narrative)
Answer:
D. This riddle was solved by the youngest student in the group.