What significant life event prompts Koly to leave her home?

Koly's departure from her home is primarily driven by her arranged marriage. In the context of the story, this event marks a pivotal moment in her life, as she transitions from the familiar confines of her childhood home to an uncertain future with her husband, whom she does not know well. This arranged marriage is significant not just as a personal milestone for Koly, but also as a reflection of cultural practices regarding marriage in her society. It highlights the lack of agency she has over her own life decisions, pushing her into a role defined by her husband's expectations and societal norms. The challenges she faces after the marriage reveal the struggles and resilience of women in similar situations, providing depth to her character and the narrative.

The other life events listed, such as education completion, family disputes, and natural disasters, do not have the same compelling impact on Koly's journey. While they may influence her life in various ways, they do not serve as the catalyst for her significant departure from her home. Instead, it is the institution of arranged marriage that fundamentally alters the course of her life and leads to her experiences of hardship and self-discovery throughout the story.