Which of the following statements about the effect of a change in tax law or rate is true? O Only an existing deferred tax asset should be adjusted and the effect shown in tax expense in the year the change is enacted. O Only an existing deferred tax liability should be adjusted and the effect shown in tax expense in the year the change is enacted. The deferred tax liability or asset should be adjusted and the effect shown in tax expense in the year the change is enacted. The deferred tax liability or asset should be adjusted and the effect shown in tax expense in the year the change becomes effective.