Which of the following are true of valuation allowances?
a. The decision to establish a deferred tax asset valuation allowance is an objective assessment.
b. The determination of the amount of a deferred tax asset valuation allowance is an objective assessment.
c. The decision to establish a deferred tax asset valuation allowance is a subjective assessment.
d. The determination of the amount of a deferred tax asset valuation allowance is a subjective assessment.