(Full question statement)Universal Containers wants Opportunities to no longer be editable when they reach the...

Comprehensive and Detailed Explanation From Exact Extract:

A (Correct):AnApproval Processcan lock a record (making it read-only) once the record meets certain criteria like stage = Closed/Won.

B (Correct):AValidation Rulecan prevent users from saving changes when the stage is Closed/Won, by throwing an error.

Example validation formula:

text

CopyEdit

AND(ISCHANGED(StageName), ISPICKVAL(StageName, "Closed Won"))

Incorrect options:

C:Before triggers run before the record is saved but don’t prevent UI-level edits unless combined with DML rollbacks or errors.

D:Auto-response rules are for sending emails, not restricting edits.