Use the following data for questions 18 to 21: Suppose in a certain year, a country has GDP = 2000, consumption C = 1200, the domestic investment I = 400, private savings S = 200, government expenditure G = 350, exports of goods and services X = 200, net primary income (investment income received from a foreign country, as well as compensation) is zero, and net unilateral transfer received is 100. What is the balance of the current account (Positive numbers mean the current account surplus, and negative numbers for deficit)? A. O B. 200 C. 150 D. -50