Your on-premises datacenter contains a server that runs Linux and hosts a Java app named App1. App1 has the following characteristics: - App1 is an interactive app that users access by using HTTPS…

Azure Batch is designed for running large-scale parallel batch jobs and is not suitable for hosting interactive web applications that require continuous availability and response.

Azure App Service is a Platform-as-a-Service (PaaS) offering ideal for hosting interactive web applications like App1. It natively supports Java apps on Linux, provides automatic scaling of instances to manage fluctuating loads, and significantly minimizes administrative effort by handling the underlying infrastructure, thus meeting all specified requirements.

Azure Kubernetes Service (AKS) manages containerized applications, but the question states App1 requires major changes to run in a container, and AKS typically involves higher administrative overhead compared to App Service for application management.

Azure Virtual Machine Scale Sets (VMSS) provide IaaS-level scaling for VMs, which requires more administrative effort for operating system, runtime, and application management compared to a PaaS solution like App Service.