Relationship between the given pair:
Arena refers to a place or scene of activity, debate
Option (A): The word confess refers to 'disclose, admit or reveal.'
Option (B): Palate separates the cavities of the mouth and nose in vertebrates.
Option (C): A Forum is a medium where ideas and views on a particular issue can be exchanged/discussed
Option (D): Belated is an antonym for timely which refers to "having been delayed; done or sent too late"
Therefore, from the given explanation, the pair that best expresses a relationship similar to that in "ARENA: DEBATE" is "Forum: Discussion".