Option B provides the simplest consolidated content-delivery architecture. Alibaba Cloud CDN can use multiple origins, and current CDN functionality supports origin-selection rules based on parameters such as request path, headers, query strings, and cookies. This allows static requests to be associated with an OSS origin while application requests are forwarded toward the ALB-backed application tier.
Static objects stored in OSS benefit directly from CDN edge caching. Requests are routed to nearby CDN points of presence, and cached resources can be returned without repeatedly accessing the OSS origin, reducing both latency and origin load.
Dynamic responses are generally not cached because they are generated uniquely for requests. They can still be routed to the application origin according to the configured origin rules.
The Global Accelerator alternatives create an unnecessarily fragmented architecture and attempt to use separate acceleration paths where one CDN-facing domain and origin-routing configuration can satisfy the question with fewer components. They also introduce additional DNS and acceleration configuration.
Therefore, a single CDN delivery layer with OSS and ALB-backed origins, combined with Alibaba Cloud DNS directing the application domain to CDN, produces the lowest configuration overhead.
Study Guide reference: Delivering Services and Content on Alibaba Cloud — CDN, OSS acceleration, ALB origins, and intelligent content delivery.
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