Which financial statement primarily indicates profitability over a specific period?

The income statement is designed to summarize a company's revenues and expenses during a specific period, typically over a fiscal quarter or year. This financial statement provides insight into the company's operational performance by showing how much profit or loss is generated from its core business activities. It includes various components like sales revenue, cost of goods sold, operating expenses, and taxes, which ultimately lead to the net income figure.

The balance sheet, while essential for understanding a company's financial position at a single point in time, does not show how much money was made or lost during the period in question. The cash flow statement focuses on the cash inflows and outflows, providing a picture of liquidity rather than profitability. The equity statement reflects changes in the equity section of the balance sheet and does not serve as a primary measure of a company's income or profitability during a period. Therefore, the income statement is the correct choice for indicating profitability over a specific timeframe.