First Principles Thinking: indirect-method operating cash flow
C is correct. Under the indirect method, add back non-cash expenses and adjust for working capital. Start with net income of USD 25, add depreciation of USD 4, subtract the USD 3 increase in accounts receivable, add the USD 2 decrease in inventory, and add the USD 1 increase in accounts payable. The result is USD 25 + USD 4 - USD 3 + USD 2 + USD 1 = USD 29.
A is incorrect because it reverses at least one working capital adjustment.
B is incorrect because it omits one of the required additions.