The correct answer is Different cloud customers sharing the same physical or virtual computing resources from a cloud provider.

The phrase Different cloud customers sharing the same physical or virtual computing resources from a cloud provider captures the essence of multitenancy because it describes multiple tenant accounts using the same underlying infrastructure while the provider enforces logical isolation between tenants. Multitenancy focuses on sharing compute, storage, or networking resources to achieve economies of scale and simplified management while still keeping tenant data and operations separate.

Cloud Identity is incorrect because it is a service for identity and access management and not a definition of how resources are shared among customers. The term refers to user and device identity controls and not to the architectural model of resource sharing.

A single customer running workloads across two or more cloud vendors is incorrect because that scenario describes multi cloud or cross cloud deployment and not multitenancy. Multitenancy is about multiple customers sharing one provider's resources rather than one customer using multiple providers.

Two independent companies federating their directory services while retaining control of their own accounts is incorrect because that describes federation or trust relationships and not multitenancy. Federation lets separate organizations share authentication or authorization but it does not mean they share the same underlying compute or storage resources.

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