As the cloud administrator for a global e-commerce platform hosted on Azure, you are tasked with ensuring the platform's high availability and optimal performance during peak shopping seasons. The platform experiences variable loads, requiring proactive monitoring of application behavior and resource utilization, along with setting up automated responses to potential issues. You must consider cost-effectiveness, scalability, and the need for detailed insights into application performance. Which Azure service would you choose to meet these requirements? (Choose the BEST option from the following four options.)