Define cost object and give three examples.

A$.$ A cost object is anything for which a separate measurement of costs is desired. Examples include a product, a service, and a customer.

B$.$ A cost object is a resource sacrificed or forgone to achieve a specific objective. Examples include direct materials, direct labour, and advertising.

C$.$ A cost object is a cost incurred $($historical or past cost$),$ as distinguished from a budgeted cost, which is a predicted or forecasted cost $($a future cost$).$ Examples include materials, labour, and overhead.

D$.$ None of the above