SIMULATION - You need to prevent administrators from performing accidental changes to the Homepage app service plan. To complete this task, sign in to the Azure portal. 

See the explanation below.

You need to configure a ˜lock` for the app service plan.A read-only lock ensures that no one can make changes to the app service plan without first deleting the lock. 1. In the Azure portal, type App Service Plans in the search box, select App Service Plans from the search results then select Homepage.Alternatively, browse to App Service Plans in the left navigation pane. 2. In the properties of the app service plan, click on Locks. 3. Click the Add button to add a new lock. 4. Enter a name in the Lock name field.It doesn`t matter what name you provide for the exam. 5. For the Lock type, select Read-only. 6. Click OK to save the changes.