You have an Azure subscription that contains the following resources:

$$ A Virtual machine named VM$1.$

$$ An App service web app named WebApp$1.$

$$ A Container app named app$1.$

You plan to deploy an Azure application gateway named GW$1.$

Which resources can you add to the GW$1$ backend pool?

WebApp$1$ only

VM$1$ and WebApp$1$ only

WebApp$1$ and app$1$ only

VM$1,$ WebApp$1$ and app$1$