A banking company uses a VIP Flag in the Contact Object that they want only...

Field-Level Security (FLS) is the most secure and efficient method to restrict visibility of sensitive fields like the VIP Flag to specific user groups or profiles. FLS is applied at the field level, ensuring that users who lack permission cannot view, edit, or access the field, regardless of the sharing or page layout configurations.

Option A: Changing the field type to a picklist and using record types unnecessarily complicates the solution. Record types are typically used for different business processes, not for field-level security.

Option B: Using page layouts restricts visibility on the UI but doesn’t secure the field from API or report-level access. Users with access to the object could still retrieve the field's data.

Option C: Setting FLS ensures that the field is hidden everywhere it appears (e.g., UI, reports, APIs) for all profiles except the Private Banking Rep Profile. This is the most effective and Salesforce-recommended method for sensitive data control.