Answer: C - Net income without deducting taxes
Operating surplus generally refers to earnings from operations less operational expenses. It does not factor in the effect of depreciation, interest or taxes.
Generally, Earnings Before Interest, Taxes, Depreciation and Amortization (EBITDA) is considered to the operating surplus. It is a very rough measure of operating cash flows.
Given this definition and the data in the question, net income without deducting taxes seems to be the most appropriate choice.