To create Intercompany Journal Entries and ensure access to the relevant subsidiaries for a Controller, the correct approach is to "Assign relevant subsidiaries to the Controller role." This assignment is crucial because it defines the scope of the Controller's access within NetSuite, specifically allowing them to interact with, create, and manage journal entries across the subsidiaries they have been granted access to. This method provides a streamlined and secure way to manage access rights, ensuring Controllers can perform their duties effectively across the designated parts of the organization without unnecessary limitations or overly broad access.References: NetSuite Help Center, Role and Access Management documentation.