recommended way to update lookup data?

Hello - I need to remove an option from the Subject dropdown on a Request.

SubjectBase appears to be the CRM db table where this metadata is stored. One way to remove this option would be to execute a delete statement in SSMS to delete this row from the table. However, I think MS generally advises against making any type of direct change on the core CRM datamodel if CRM provides an alternate way to make this change through the CRM UI.

So does CRM provide a way to maintain this type of metadata through the CRM UI? If so then can you point me to where this update should be made?