You are tasked with implementing column-level security on the 'EMPLOYEE table to restrict access to the 'SALARY column. Only users with the 'HR ROLE' should be able to view the actual salary. All other users should see NULL. You create a masking policy as follows:

What additional steps are necessary to enforce this policy?
Correct Answer: B
The masking policy itself defines the logic, but it needs to be applied to the specific column. The 'ALTER TABLE ... MODIFY COLUMN ... SET MASKING POLICY statement is the correct way to associate the policy with the 'SALARY column. Option A is incorrect because APPLY MASKING POLICY is required only if the policy needs to reference another object that the user does not own. Options C, D and E are unrelated to correctly applying a masking policy at the column level.