The word "madness" in the context of the sentence suggests a sense of chaos or frenzied excitement associated with the carnival season. The sentence that has a connotation most similar to this idea of chaos is:
C. Gritting her teeth, Naomi prepared for chaos as she entered the bustling bus station at the peak of the afterschool release rush.
Here, "chaos" conveys a similar sense of disorder and tumult, akin to "madness" in the context of the carnival.