Options A, B, and C are consistent with the fundamental characteristics and enabling technologies of cloud computing. Cloud platforms are designed to make resources elastic. Huawei Cloud Auto Scaling, for example, dynamically adds or removes ECS instances and adjusts related resources according to actual workload demand. Dynamic resource scaling is therefore a core practical capability of cloud computing.

On-demand deployment is also fundamental. Huawei Cloud's Cloud Adoption Framework explains that cloud resources can be provisioned, adjusted, and scaled rapidly without the traditional procurement and installation cycle associated with physical infrastructure. This allows organizations to create computing environments when needed and release them when demand decreases.

Virtualization is another important enabling technology. It allows physical computing resources to be abstracted, pooled, isolated, and efficiently shared among multiple workloads. Huawei Cloud specifically identifies virtualization and resource pooling as mechanisms that improve physical-resource utilization.

Option D is incorrect. A defining cloud characteristic is that the provider assumes responsibility for substantial portions of infrastructure construction and maintenance. The exact customer/provider boundary varies between IaaS, PaaS, and SaaS, but customers do not maintain all resources .

Reference topics: Cloud Computing Characteristics; Elasticity; On-Demand Provisioning; Virtualization; Shared Responsibility.

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