Terminate Work Relationship: Change Reason default and make required

Summary

Have Reason appear as a blank then make user select a reason.

Content

Hello all!

We have a request from the Director of Human Resources:

"Currently when a manager goes into submit a resignation in the system, the Reason field defaults to Personal Reasons.  And Managers are not using the drop down to identify the proper reason for the resignation.
 
Can we do 2 things with this field:
1.      Make it default to a blank or “select from dropdown”
2.      Make it required for them to select something from the drop down list
 
We are trying to use the Reason field for reporting and it isn’t accurate."