Which role is required to edit backup configuration in SDDC Manager?

C is the correct answer. See Student Book:
10-9 Scheduling File-Based Backups for SDDC Manager

To configure file-based daily backups of the SDDC Manager instances using the SDDC Manager administration interface:
1. In the navigation pane, click Administration > Backup.
2. On the Backup page, click the SDDC Manager Configurations tab. 3. Under Backup Schedule, click Edit. 4. On the Backup Schedule page, enter the settings and click Save. 5. To verify the backup, click Backup Now.
Only users with the Admin role can perform this task