How is a Poll scope's watermark accessed from a message processor in a flow?

• A. In a flow variable named watermark
• B. As a flow property
• C. As a header property
• D. In a flow variable

Answer: (D)

The watermark from the Poll scope is exposed as a flow variable, so it can be read by any processor inside the flow using the flowVars map. Inside a processor you’d typically access it with an expression like #[flowVars.watermark], which retrieves the last poll position. This keeps the poll's state local to the flow instance and avoids mixing with message headers or flow properties, which serve different purposes. If you see a different variable name for the watermark in your flow, use that name, but the mechanism remains: read the value from a flow variable rather than a property or header.