Individual metrics without a specified service context are unhelpful. They should relate to defined outcomes and not simply operational metrics. This can be achieved with balanced bundles of metrics, such as customer satisfaction and key business outcomes.

https://www.bmc.com/blogs/itil-service-level-management/#:~:text=Service%20Level%20Agreements%20(SLAs) & text=Individual%20metrics%20without%20a%20specified,satisfaction%20and%20key%20business%20outcomes.

The organizations and people dimension sets out the people aspects of service management to be considered when designing, operating and changing service offerings. People include employees, managers, executives, customers, supplier employees, or anybody else who is involved in the creation or consumption of services.

https://assyst.ifs.com/blog/itil4-organizations-and-people#:~:text=The%20organizations%20and%20people%20dimension%20sets%20out%20the%20people%20aspects,creation%20or%20consumption%20of%20services.

Service desks provide a variety of channels for access including:

Phone calls, which can include specialized technology, such as interactive voice response (IVR), conference calls, voice recognition, and others.

Service portals and mobile applications, supported by service and request catalogues, and knowledge bases.

Chat, through live chat and chatbots.

Email for logging and updating, and for follow-up surveys and confirmations.

Walk-in service desk (which are becoming more prevalent in some sectors, such as higher education, where there are high peaks of activity that demand physical presence).,

Text and social media messaging, which are useful for notifications in case of major incidents and for contacting specific stakeholder groups, but can also be used to allow users to request support.

Public and corporate social media and discussion forums for contacting the service provider and for peer-to-peer support.

https://www.bmc.com/blogs/itil-service-desk/

In ITIL 4, the purpose of the information security management practice is to:

Protect the organization’s information by ensuring confidentiality, integrity, and availability of data, and also covering aspects such as authentication, non-repudiation, and reliability.

Authentication ensures that users or systems are who they claim to be.

Non-repudiation ensures that an action or transaction cannot later be denied by the party that performed it.

These are core topics within information security controls and are explicitly associated with the information security management practice.

Why the other options are incorrect:

Change enablement – Focuses on ensuring that changes are properly assessed, authorized, and managed to maximize value and reduce risk; it does not specifically manage authentication or non-repudiation.

Service configuration management – Ensures that accurate and reliable information about configuration items (CIs) and their relationships is available; it is not primarily about security controls like authentication and non-repudiation.

IT asset management – Manages IT assets to maximize value and control costs and risks; again, not about authentication or non-repudiation as a primary purpose.

Therefore, the practice whose purpose includes managing authentication and non-repudiation is information security management.

“Service desk staff require training and competency across a number of broad technical and business areas. In particular, they need to demonstrate excellent customer service skills such as empathy, incident analysis and prioritization, effective communication, and emotional intelligence.

https://www.servicedeskinstitute.com/the-case-for-itil4-foundation-service-desk-analyst-training/#:~:text=%E2%80%9CService%20desk%20staff%20require%20training,effective%20communication%2C%20and%20emotional%20intelligence.