Which elements are part of a Mule 3 message structure?

• A. Mule message ( [Inbound properties], [Outbound properties], [payload], [Attachments])
• B. Mule message ( [Headers], [Payload], [Attachments])
• C. Mule message ( [Inbound properties], [Payload] )
• D. Mule message ( [Inbound properties], [Outbound properties], [Payload], [Custom fields])

Answer: (A)

In Mule 3, a message is a container that carries both data and metadata as it flows through components. The four main parts are inbound properties (metadata that comes with the message from the transport, such as source details and content type), the payload (the actual data being processed), outbound properties (metadata set for when the message leaves the flow, like response headers), and attachments (binary data attached to the message). This four-part structure is why the correct choice lists inbound properties, outbound properties, payload, and attachments. Other options mix in elements like headers as a separate section or omit attachments or include non-standard fields, which isn’t how a Mule 3 message is organized.