What defines the responsibility difference between a data owner and a data custodian?

The distinction between the responsibilities of a data owner and a data custodian is crucial in governance, risk, and compliance frameworks. In this context, the data owner is responsible for determining the classification and handling of data according to its sensitivity and importance. The data owner is the entity that has the authority and accountability for the data, deciding how it should be classified and used within the organization.

Once the data owner has established the classification scheme, it's the responsibility of the data custodian to implement this scheme effectively. The custodian’s role is primarily focused on the operational aspect of managing data, ensuring that the handling, storage, and access controls are in compliance with the guidelines set forth by the data owner. Therefore, the statement indicating that the data custodian implements the classification scheme after it has been initially assigned by the data owner accurately reflects the division of responsibilities between these two roles.

This clear separation helps establish effective governance, ensuring that there is accountability for decision-making (data owner) and operational execution (data custodian). The other options present misunderstandings of these roles, conflating the responsibilities and suggesting an inaccurate flow of authority or implementation.