Business impact analysis (BIA) is the most helpful tool in identifying loss magnitude during risk analysis of a new system, as it involves estimating the potential financial and operational losses resulting from the disruption or degradation of the system. Recovery time objective (RTO), cost-benefit analysis, and cyber insurance coverage are not the most helpful tools, as they are more related to the recovery, evaluation, andtransfer of the risk, respectively, rather than the identification of the loss magnitude. References = CRISC Review Manual, 7th Edition, page 108.