Answer:
B). The relationships the main character has with other characters.
Step-by-step explanation:
The theme in literature is demonstrated as the central idea, claim, or message of the author displayed through a literary work. It is exemplified as the fundamental element of the narrative that serves to unify the text as a whole and provide the audience with a better understanding by revealing the conflicts, actions, explorations, etc.
As per the question, the element that aids to identify the theme of a story would be 'the relationships the main character has with other characters' as these relationships drive the plot by leading to the development of conflicts due to several reasons like emotional attachments(positive or negative) resulting in possessiveness, misunderstandings, anger, etc. The theme of the narrative is built around this structure. Thus, option B is the correct answer.