The bystander effect, a well-documented social psychological phenomenon, posits that individuals are less likely to intervene in an emergency situation when others are present. This counterintuitive behavior is often attributed to a complex interplay of diffusion of responsibility, where individuals feel less personal obligation, and pluralistic ignorance, where each person privately rejects the situation as an emergency but infers from others' inaction that no intervention is needed. Consequently, in public spaces or online environments where observers are numerous and often anonymous, the likelihood of a person receiving timely assistance can paradoxically diminish despite the abundance of potential helpers.

Which of the following sentences best completes this paragraph?

A. Thus, addressing these inherent psychological hurdles is paramount for fostering proactive engagement and improving outcomes in critical situations.
B. Early experiments by Darley and Latané conclusively demonstrated the effect's robustness in controlled laboratory settings.
C. This phenomenon, while primarily studied in Western societies, appears to manifest similarly across diverse cultural contexts.
D. Moreover, the increased prevalence of smartphones has further complicated the role of bystanders, sometimes leading to documentation rather than intervention.