When an administrator in a child domain attempts to modify a record (such as a policy or business rule) that belongs to a parent or global domain, the system prevents direct modification. Instead, it creates a copy of the record in the administrator's current domain. This new record is called an override. To maintain the relationship between the original record and the new override, the system automatically populates the sysoverrides field on the new record with the sysid of the original record. This allows the system to use the domain-specific version for users in that domain.

B. sysprimarydomain: This is not a standard system field used in the domain override process.

C. sysadmindomain: This is not a standard system field used in the domain override process.

D. sysdomainowner: This is not the correct field name. The standard field that links an override to the original record is sysoverrides.

1. ServiceNow Product Documentation - Domain Separation Explained: In the section "How domain separation works," the documentation details the override process: "When a user in a child domain modifies a record from a parent or global domain, the system creates a copy of the record in the child domain. This copy is called an override. The system then adds a reference to the original record in the sysoverrides field on the new record."

2. ServiceNow Product Documentation - Dictionary Overrides: The documentation on Dictionary Overrides explains the function of the sysoverrides field, stating, "The Overrides field (sysoverrides) contains the sysid of the record it overrides." This confirms the field's purpose in linking a domain-specific version to its global or parent counterpart.