You create an App Service plan named App1 and an Azure web app named webapp1. You discover that the option to create a staging slot is unavailable. You need to create a staging slot for App1.
What should you do first?
A . From webapp1, modify the Application settings.
B . From webapp1, add a custom domain.
C . From App1, scale up the App Service plan.
D . From App1, scale out the App Service plan.
Answer: C
Explanation:
Scale up: Get more CPU, memory, disk space, and extra features like dedicated virtual machines (VMs), custom domains and certificates, staging slots, autoscaling, and more.
You scale up by changing the pricing tier of the App Service plan that your app belongs to.
Reference: https://docs.microsoft.com/en-us/azure/app-service/manage-scale-up