The type of risk that is most likely to materialize as a result of allowing several employees to retire early in order to avoid layoffs is institutional knowledge loss, as it represents the loss of valuable information, experience, and expertise that the employees have accumulated over time, and that may not be easily transferred or replaced. Confidentiality breach, intellectual property loss, and unauthorized access are not the most likely types of risk, as they are more related to the security, ownership, or access of information, respectively, rather than the retention or transfer of knowledge. References = CRISC Review Manual, 7th Edition, page 100.