A Deployment has enough spare cluster capacity. During an update, the team requires all existing replicas to remain available while a replacement Pod becomes ready. Which rolling-update settings fit this requirement?

1. maxUnavailable: 0 and maxSurge: 1
2. maxUnavailable: 100% and maxSurge: 0
3. Set replicas to zero before changing the image
4. strategy.type: Recreate