Which of the following is an essential feature of employee self-service in Oracle HCM Cloud?

The essential feature of employee self-service in Oracle HCM Cloud is the access to personal and work-related data. This functionality empowers employees by allowing them to view and manage their own information, such as personal details, employment history, and benefits. By providing this level of access, employees can take responsibility for their own records and ensure that their information is accurate and up-to-date. This is particularly beneficial in fostering a culture of transparency and enabling employees to engage more actively with their employment data.

The other options do not align with the purpose of employee self-service in the same way. For instance, conducting salary negotiations, approving other employees' requests, and modifying company policies are typically reserved for managerial or HR roles, as they involve authority and decision-making that go beyond the capabilities of individual employees within the self-service framework. By focusing on personal and work-related data, Oracle HCM Cloud enhances employee involvement and satisfaction while maintaining appropriate boundaries regarding authority and decision-making within the organization.