Key performance indicators in compliance regulation and risk assessment typically include metrics that directly relate to the financial and reputational consequences of non-compliance. Fines or penalties (A) directly measure financial repercussions of regulatory violations. Customer complaints (B) are a critical indicator of potential compliance issues, as they can flag problems that may require regulatory scrutiny. While regulatory criticism (C) can indeed be a key indicator, it is not inherently a performance metric as it is more a qualitative assessment than a quantifiable KPI. Therefore, options A and B are the most applicable KPIs in this context.