You need a fully managed platform so developers can focus on code for a global, high-scale photo upload/share app serving millions of concurrent users. Which Google Cloud service should you use?

App Engine is the correct choice because it is a fully managed, serverless platform designed for developing and hosting highly scalable web applications and mobile backends. It automatically handles infrastructure provisioning, scaling, and maintenance, allowing developers to focus solely on writing code. This aligns perfectly with the requirement for a global, high-scale photo upload/share app serving millions of concurrent users without managing servers. Cloud Endpoints is incorrect because it's an API management tool, not a platform for hosting the application itself. Compute Engine is incorrect as it provides IaaS (Infrastructure as a Service), requiring manual management of VMs, scaling, and patching, which contradicts the "fully managed" requirement. Google Kubernetes Engine (GKE) is incorrect because while powerful for container orchestration, it still requires more operational overhead for cluster management compared to the fully serverless App Engine.