How should a developer set up the files before making required edits to the address...

Locale-specific SFRA form structures are implemented usinglocale directories beneath the cartridge ' s forms directory, while keeping the form-definition filename unchanged. Therefore, the appropriate structure is:

cartridge/forms/en_US/address.xml

Salesforce ' s official Forms documentation explicitly states that to change the structure of a form by locale, developers create locale-specific folders and store a form definition with thesame nameinside each locale folder. Theforms/defaultdefinition acts as the fallback when no locale-specific version exists.

Option A incorrectly tries to encode the locale in the XML filename. Option C places the file in an unsupportedxmlsdirectory.

Study Guide reference:Application Development — localized forms,forms/en_US,forms/default, form structure localization, and address forms.

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