フリー問題

問題文

A flow starts with an HTTP Listener at path /report. A caller sends GET /report?region=east. The next component must read the value east into a Logger message. Which expression reads it?

選択肢

1. An expression that reads vars.region, because the listener creates one variable per query parameter.
2. An expression that reads attributes.queryParams.region, because the listener puts the parsed query string into the attributes of the message.
3. An expression that reads attributes.uriParams.region.
4. An expression that reads payload.region.