To automate the process of sending an email notification to the customer when a support rep at Ursa Major Solar closes a case, the following settings should be used:
* Case Close Template in the Support Settings: This feature allows the administrator to define a standard email template that will be automatically sent to the contact associated with the case when it is closed. This ensures consistency in communication and reduces the manual effort required by the support reps.
* Notify Contact Checkbox on Close Page Layout: Adding this checkbox to the case close page layout gives the support reps the option to send an email notification to the contact when closing a case. If the checkbox is checked, the email notification (defined by the case close template) will be sent.
The other options, B (Auto response rule step set 'or status of closed') and D (Add the Knowledge component to the closed layout), do not directly address the requirement of sending an email notification when a case is closed.
References:
* Salesforce Help: Automate Case Management
* Salesforce Help: Case Support Settings