Which of the following is the BEST definition of an Incident?

A.
Loss of ability to operate to specification, or to deliver the required output

B.
A change of state which has significance for the management of a Configuration Item or
IT Service

C.
A warning that a threshold has been reached, something has changed, or a failure has
occurred

D.
An unplanned interruption to an IT service or reduction in the quality of an IT service