Following a significant change to a business process, the risk practitioner should advise the risk owner to first conduct a risk analysis to evaluate the current level of risk exposure and compare it with the previous level. This will help to verify whether the change has indeed reduced the risk, and by how much. The risk analysis will also help to identify any new or residual risks that may have emerged as a result of the change. The other options are not the first actions to take, but rather the subsequent steps after conducting a risk analysis. Reviewing the key risk indicators, updating the risk register, and reallocating risk response resources are all important activities, but they depend on the outcome of the risk analysis. References = CRISC EXAM TOPIC 2 LONG; CRISC Q&A Domain 1; Managing Change Risk - Oliver Wyman