Which of the following financial metrics indicates how much profit each share of stock earns?

Earnings Per Share (EPS) is a financial metric that specifically measures the profit attributable to each outstanding share of a company's stock. It is calculated by dividing the company's net earnings by the number of shares outstanding. This figure is crucial for investors as it provides a clear idea of the company's profitability on a per-share basis, allowing for easier comparison with other companies and industry averages.

The other metrics mentioned do not specifically provide insight into profit per share. Return on Investment (ROI) measures the performance of an investment relative to its cost, while Return on Equity (ROE) assesses a firm's profitability in relation to shareholders’ equity. The Quick Ratio, on the other hand, is a liquidity measure used to evaluate a company's ability to meet short-term obligations without relying on the sale of inventory. Thus, EPS stands out as the most relevant metric for understanding earnings per share.