Final answer:
Page Value is the most useful metric for ranking pages based on their revenue contribution as it reflects the value of a page in the process of generating e-commerce revenue.
Step-by-step explanation:
The Page Value metric would be most useful for ranking pages according to their revenue contribution. Page Value represents the average value for a page that a user visited before completing an e-commerce transaction. This metric assigns a value to different pages based on their role in the conversion path and the revenue they help to generate.
Bounce Rate is the percentage of visitors who navigate away from the site after viewing only one page, which does not directly relate to revenue. Revenue is the total income but does not provide insight into the individual page's contribution. ROI (Return on Investment) measures the gain or loss generated on an investment relative to the amount invested, which is more appropriate for evaluating the overall financial return of a campaign or business area. Margin refers to the difference between the revenue and the cost of goods sold, which again doesn't attribute value to individual pages.