How can you modify&#

How can you modify the application to return more meaningful error messages to the user?（）

• ACreate a custom messages table. Include the necessary error handling code in the form modules to display the meaningful custom message instead of the ORA- error message. 
• BProvide users with a form in the application to query the ORA- error, that will return a custom message to replace the ORA- message. 
• CEliminate constraints where possible, thereby limiting the number of error messages returned. 
• DCreate a procedure to include the RETRIEVE_MESSAGE built-in that automatically translates common server errors into meaningful messages for use in Forms.