Final answer:
Gross profit is the item that appears on both a single-step and a multiple-step income statement, as it is a key measure of a company's profitability before overhead costs. Thus, the correct option is C.
Step-by-step explanation:
The item that appears on both a single-step and a multiple-step income statement is C. Gross profit. Both types of income statements calculate gross profit by subtracting the cost of goods sold from revenues or net sales. Gross profit shows the profitability of a company's core business activities before overhead costs, and it is an essential component for analyzing a company's financial health.
Inventory is reported on the balance sheet rather than the income statement. Income from operations is a line item on a multiple-step income statement that provides insight into a company's operational efficiency by excluding non-operating activities. However, it does not appear as a separate line in a single-step income statement.