A company wants to host a customer-facing app that requires high availability and automatic scaling. Which Azure service best meets this need?

Azure App Service is the best choice because it's a fully managed platform for building, deploying, and scaling web apps. It inherently provides high availability and built-in auto-scaling capabilities, making it ideal for customer-facing applications with fluctuating demand. Azure Logic Apps is for workflow automation and integration, not hosting web applications. Azure Virtual Network provides network isolation and connectivity, but doesn't host applications or provide scaling. Azure Blob Storage is for storing unstructured data, not for running application code.