Provisions

Dear Sir, when I was revising the IAS 37 Chapter, I encountered this question:

In a review of its provisions for the year ended 31 March 2015, Cumla’s assistant accountant has suggested the
following accounting treatments:

(i)
Making a provision for a constructive obligation of $400,000; this being the sales value of goods expected to be returned by retail customers after the year end under the company’s advertised 30-day returns policy

(ii)
Based on past experience, a $200,000 provision for unforeseen liabilities arising after the year end

(iii)
The partial reversal (as a credit to the statement of profit or loss) of the accumulated depreciation provision on an item of plant because the estimate of its remaining useful life has been increased by three years

(iiii)
Providing $1 million for deferred tax at 25% relating to a $4 million revaluation of property during March 2015 even though Cumla has no intention of selling the property in the near future

Which of the above suggested treatments of provisions is/are permitted by IFRS?

A (i) only
B (i) and (ii)
C (ii) and (iii)
D (iv)

The answer is D. Could you explain to me why (i), (ii) and (iii) are not treated as provisions? Thank you!