In "The Crow Child" by Mary Males Doge, Rita can tell that Cora is a complex character through several indicators, but the option that best highlights Cora's complexity is:
She has the most to lose if the problem is not solved.
This suggests that Cora's motivations, fears, and stakes are deeply intertwined with the story's central conflict. Characters with significant stakes often have layered personalities, internal struggles, and nuanced relationships with other characters, which contribute to their complexity.