To secure inter-cluster communication with Istio, you need to enable Mutual TLS (mTLS) authentication. This ensures that all communication between services, even across different clusters, is encrypted and verified. Options A and B are partially correct but dont cover the full scope of inter-cluster security. Option C is not recommended as it creates complexity in managing multiple control planes. Option E is used for managing ingress and egress traffic but doesn't directly address inter-cluster security

Kubernetes manages containers and their orchestration. While it can interact with databases, Database' is not a native Kubernetes resource type. The other options (Pod, Deployment, Service, Ingress) are all core Kubernetes resources.

The 'replicas' field in a Deployment specifies the number of Pods that should be created and maintained by the Deployment. It controls the desired number of running instances of the application. If a Pod fails, the Deployment will automatically create a new Pod to replace it, ensuring that the desired number of replicas is maintained.

Istio's AuthonzationPolicy feature allows you to define granular authorization rules based on request attributes, including headers, user identities, and other context. This enables you to control access to microservices based on specific conditions. Option A is for authentication, not authorization. Option C is for traffic management. Option D is for telemetry. Option E is for service discovery and configuration.