HOTSPOT
You create a virtual network named fabVNet01.
You design the virtual network to include two subnets, one named DNS-subnet and one named Appssubnet, as shown in the exhibit. (Click the Exhibits button.)
In the table below, identify the number of IP addresses that will be available for virtual machines (VMs) or
cloud services in each subnet. Make only one selection in each column.
Answer: 
Explanation:
About Virtual Network Settings in the Management Portal
URL: http://msdn.microsoft.com/en-us/library/azure/jj156074.aspx
App-Subnet –> 3
DNS -subnet –> 27
I agree
app_subnet /29=>2^3-5=3
DNS_subnet /27=>2^5-5=27,
first 3 ips and last ip are not available in azure for machine
see screen below
Are there any restrictions on using IP addresses within these subnets?
Yes. Azure reserves some IP addresses within each subnet. The first and last IP addresses of the subnets are reserved for protocol conformance, along with 3 more addresses used for Azure services.
updated link for the ARM portal:
https://docs.microsoft.com/en-us/azure/virtual-network/virtual-networks-create-vnet-arm-pportal
The answer remains correct as the functionality is the same.