In which scenario is a Declare OnChange rule appropriate?

In which scenario is a Declare OnChange rule appropriate?
A . When a user updates their address, the active case is suspended until the address can be confirmed.
B . During a nightly backup process, only updated fields are backed up.
C . When a developer changes a view, the change is checked into a development branch.
D . When a manager approves a case, the case is routed back to the appropriate caseworker.

Answer: A