An administrator must make the Caller field read only on the Incident form whenever State is Closed. No calculation, no message to the user and no server side enforcement is required. Which choice is the appropriate tool, and for what reason?
- AAn onLoad client script, because a script is required to read the State value while the form is rendering and set the Caller field accordingly.
- BA before business rule that sets the Caller field to read only, because server side logic controls how fields behave when the record is presented.
- CA UI policy with a read only action on the Caller field and a condition of State is Closed, because it satisfies the requirement without any code. Correct
- DAn access control rule granting write on the Caller field to holders of the itil role, because access control governs when a field may be edited.
Why A is wrong: Tempting because an onLoad script can set a field read only, but it would only act at load time and it writes code for behaviour the platform configures declaratively.
Why B is wrong: Tempting because before rules run on save and can alter a record, but business rules act on data rather than on the appearance of fields in the browser.
Why C is correct: Correct because a UI policy is the declarative tool for mandatory, read only and visible field state, and it re-evaluates as the State value changes on the form.
Why D is wrong: Tempting because a write rule does make a field uneditable for some users, but it keys on role and record conditions for security rather than on form state for usability.