How do you define a default path in a Choice router using otherwise?

• A. Add an otherwise block at the end of the Choice to catch any conditions not matched by previous when blocks.
• B. Place a when block at the beginning to catch all.
• C. Use a foreach to define a default path.
• D. Defaults are not possible in a Choice router.

Answer: (A)

In a Choice router, you define several branches with when expressions to route messages based on conditions. The default path is provided by an otherwise block placed at the end. It acts as a catch-all: if none of the previous when conditions match, the flow takes the otherwise path. This ensures there’s always a defined route and prevents the router from having no match.

Think about how routing works: Mule evaluates branches in order and takes the first one that matches. If you put a when condition that always evaluates to true at the start, every message would go there and the more specific conditions would never be reached. A foreach is not used to define a default route; it serves a different purpose—iterating over a collection. And defaults do exist precisely to handle unmatched cases, so the otherwise block is the correct mechanism.