Cloud-native applications are typically designed to thrive in dynamic, distributed environments where infrastructure is elastic and failures are expected. The best set of characteristics listed is Resiliency, Agility, Operability, Observability, making D correct.
Resiliency means the application and its supporting platform can tolerate failures and continue providing service. In Kubernetes terms, resiliency is supported through self-healing controllers, replica management, health probes, and safe rollout mechanisms, but the application must also be designed to handle transient failures, retries, and graceful degradation.
Agility reflects the ability to deliver changes quickly and safely. Cloud-native systems emphasize automation, CI/CD, declarative configuration, and small, frequent releases-often enabled by Kubernetes primitives like Deployments and rollout strategies. Agility is about reducing the friction to ship improvements while maintaining reliability.
Operability is how manageable the system is in production: clear configuration, predictable deployments, safe scaling, and automation-friendly operations. Kubernetes encourages operability through consistent APIs, controllers, and standardized patterns for configuration and lifecycle.
Observability means you can understand what's happening inside the system using telemetry-metrics, logs, and traces-so you can troubleshoot issues, measure SLOs, and improve performance. Kubernetes provides many integration points for observability, but cloud-native apps must also emit meaningful signals.
Options B and C include items that are not "characteristics" (containerd is a runtime; Kubernetes is a platform). Option A includes "availability," which is important, but the canonical cloud-native framing in this question emphasizes the four qualities in D as the foundational build characteristics.
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