To perform incremental backups using the webgisdr tool, point-in-time recovery must be enabled on the relational data store. This creates transaction logs needed for differential backups and aligns with best practices for enterprise-level backup strategies.

From Esri documentation:

''Incremental backups can only be used with a relational data store when point-in-time recovery is enabled. This enables transaction log capture needed for delta backups.''

Option A is unrelated to backup functionality.

Option C is not required unless performance tuning is needed.

ArcGIS Enterprise -- Enabling Point-in-Time Recovery in ArcGIS Data Store for Incremental Backups

=====================