Your company is designing an application architecture for Azure App Service Environment (ASE) web apps as shown in the exhibit. (Click the Exhibit tab.)

Communication between the on-premises network and Azure uses an ExpressRoute connection.
You need to recommend a solution to ensure that the web apps can communicate with the on-premises application server. The solution must minimize the number of public IP addresses that are allowed to access the on-premises network.
What should you include in the recommendation?