Which option is a Platform-as-a-Service (PaaS) offering?

• A. Microsoft Azure Virtual Machines
• B. Google App Service
• C. Google Mail
• D. Infrastructure as a Service

Answer: (B)

Platform-as-a-Service provides a ready-to-use development and runtime environment where you can deploy and scale your applications while the provider manages the underlying infrastructure, operating system, and middleware. The option described as a PaaS offering fits this by giving you an environment to run your app, with built-in scaling and managed services, so you focus on writing code rather than provisioning servers. The other choices don’t fit because one involves deploying and managing raw virtual machines (that’s IaaS), another is a consumer-facing email service (that’s SaaS), and the last is simply naming the category for IaaS rather than offering a platform for app development.