Which of the following terms is more suitable to describe the functionality of a service?

Comprehensive and Detailed Explanation From Exact Extract of ITIL 4 Managing Professional Transition:

ITIL 4 defines Utility as:

“The functionality offered by a product or service to meet a particular need.”

Utility is often described as ‘fit for purpose’.

It refers to what the service does — the features or functions that support desired outcomes.

Warranty, by contrast, is about how the service performs — its availability, capacity, security, etc.

Output is a deliverable or result of an activity.

Outcome is a result for a stakeholder enabled by one or more outputs.Thus, Utility most directly represents the functionality of a service, making Option C correct.