Which element do you use to reference a properties file in a Mule application?

• A. Property Placeholder element
• B. Inbound Endpoint
• C. DataWeave Transform
• D. Flow Reference

Answer: (A)

Externalized configuration values are brought into a Mule app with a Property Placeholder. This element reads a properties file (for example, config.properties) and exposes each key as a placeholder you can reference throughout the config using ${key}. This lets you configure endpoints, credentials, and other settings outside the flows, making it easy to swap values for different environments without changing the code.

For instance, with a file containing api.url=https://api.example.com, you load it via the Property Placeholder and then use ${api.url} wherever that value is needed in your connectors or other components. That separation of configuration from logic is what Property Placeholder enables.

The other options are different concepts: Inbound Endpoint is about receiving messages, DataWeave Transform handles data transformation, and Flow Reference calls another flow. None of these load or substitute values from a properties file.