Since the question is looking for the highest likelihood that an unauthorized user will be denied access. The organization will side with the biometric solution that, in this case, would provide the most security. The False Acceptance Rate (FAR) metric determines the number of instances where unauthorized persons were incorrectly authorized. Making sure the False Acceptance Rate is low means a lower possibility for someone to be authorized who shouldn't. This would provide the security the organization is looking for. The Crossover Error Rate(CER) describes the point where the FRR and FAR are equal showing the accuracy of a biometric system. The accuracy/sensitivity of biometric system is not what the organization is concerned with, only the security the solution provides.