B is correct. A cloud native application is designed to be scalable, resilient, and adaptable, and to leverage cloud/platform capabilities rather than merely being “hosted” on a cloud VM. Cloud-native design emphasizes principles like elasticity (scale up/down), automation, fault tolerance, and rapid, reliable delivery. While containers and Kubernetes are common enablers, the key is the architectural intent: build applications that embrace distributed systems patterns and cloud-managed primitives.

Option A is not enough. Simply containerizing a monolith and running it in the cloud does not automatically make it cloud native; that may be “lift-and-shift” packaging. The application might still be tightly coupled, hard to scale, and operationally fragile. Option C is too narrow and prescriptive; cloud native does not require “all functions in separate containers” (microservices are common but not mandatory). Many cloud-native apps use a mix of services, and even monoliths can be made more cloud native by adopting statelessness, externalized state, and automated delivery. Option D is too broad; “any app running in a cloud provider” includes legacy apps that don’t benefit from elasticity or cloud-native operational models.

Cloud-native applications typically align with patterns: stateless service tiers, declarative configuration, health endpoints, horizontal scaling, graceful shutdown, and reliance on managed backing services (databases, queues, identity, observability). They are built to run reliably in dynamic environments where instances are replaced routinely—an assumption that matches Kubernetes’ reconciliation and self-healing model.

So, the best verified definition among these options is B.

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