Final answer:
To enable the Follow the sun field on the Customer Service Case form, the '.csm_time_recording' plugin must be activated. Additionally, the field may need to be added to the case form manually.
Step-by-step explanation:
To enable the Follow the sun field on the Customer Service Case form, it is not sufficient to merely set a value property to true or assume that it is a standard field. Instead, there are specific requirements that must be fulfilled. Primarily, the correct answer is that C. The plugin ' .csm_time_recording' needs to be activated on your ServiceNow instance.
Once the plugin is activated, you might also need to ensure that the Follow the sun field is properly added to the Customer Service Case form. This could involve customization or configuration within the form designer to display the field to users, depending on how your instance of ServiceNow is set up and whether the field was included by default in the layout.