please give me right answer thanks ! single choice

Which of the following is true in relation to IAS 16 Property, Plant and Equipment?

a.Day-to-day servicing cost are recognised in the carrying amount of the property, plant and equipment

b.Upon disposal of an item of property, plant and equipment, its attributable revaluation surplus (if any) may be transferred to profit or loss

c.Entities cannot change their accounting policy from the cost model to the revaluation model

d.If an item of property, plant and equipment is revalued, all property, plant and equipment of the same class must be revalued