How can an error message be returned from the document validator adaptor on a form to help
diagnose an issue?

A.
Return the message from the adaptor in a string instead of returning true or false.

B.
Return an error code from the adaptor and map that error code to an error message in Forms
Builder.

C.
Throw an exception from the adaptor with the error message.

D.
Use the Message Manager to return the string.