Step 4: Evaluate the other options to ensure they do not match the definition of the four main KPIs. For instance, 'Current Assets, Fixed Assets, Current Liabilities, and Long-term Liabilities' refers to components of the balance sheet, not KPI categories. Similarly, 'Net Income, Gross Profit, Operating Cash Flow, and Equity' and 'Revenue, Expenses, Assets, and Liabilities' are financial metrics but do not represent the four main KPI categories.