AZ400-Q: deploy a breaking API change
An API change removes a field used by an older mobile app version. Clients update slowly. What is the safest release plan?
- A) Introduce a backward-compatible API version or deprecation period, measure client adoption, then retire the old field/version after criteria are met. ✓
- B) Remove the field immediately and blame outdated clients.
- C) Skip tests because the server compiles.
- D) Change the storage account tier.
Answer: A. Compatibility and measured migration reduce customer impact when clients cannot update in lockstep.
Why not the others: Immediate removal and missing tests create avoidable breakage; storage tier is unrelated.