A cross-account incident response team must investigate workloads without maintaining long-lived keys in every account. Which approach is preferred?

1. Wait until an incident to discover whether any responder can access the account.
2. Share each account root password in the incident chat channel.
3. Preprovision scoped response roles with controlled trust, auditable assumption, and tested access.
4. Create permanent access keys for all responders in every account and never rotate them.