A draft statement of cash flow

A draft statement of cash flows contains the following calculation of cash flows from operating activities: $m Profit before tax 13 Depreciation 2 Decrease in inventories (3) Decrease in trade and other receivables 5 Decrease in trade payables 4 Net cash inflow from operating activities 21 Which of the following corrections need to be made to the calculation? 1 Depreciation should be deducted, not added. 2 Decrease in inventories should be added, not deducted. 3 Decrease in receivables should be deducted, not added. 4 Decrease in payables should be deducted, not added
A、1 and 3
B、2 and 3
C、1 and 4
D、2 and 4