Which of the following statements about IAS 2 Inventories is not correct?

A、
Production overheads should be included in cost on the basis of a company's normal level of activity in the period. ;
B、In arriving at the net realisable value of inventories, trade discounts and settlement discounts must be deducted.;
C、 In arriving at the cost of inventories, FIFO, LIFO and weighted average cost formulas are acceptable.;
D、 It is permitted to value finished goods inventories at materials plus labour cost only, without adding production overheads.