The best way to validate whether controls to reduce user device vulnerabilities have been implemented according to management's action plan is to rescan the user environment, as it provides an objective and reliable way to measure and verify the effectiveness and adequacy of the controls, and to detect any remaining or new vulnerabilities. Surveying device owners, requiring annual end user policy acceptance, and reviewing awareness training assessment results are not the best ways, as they may not provide sufficient assurance, evidence, or timeliness of the control validation, respectively. References = CRISC Review Manual, 7th Edition, page 154.