You manage a cloud service that has a web role named fabWeb. You create a virtual network named fabVNet
that has two subnets defined as Web and Apps.
You need to be able to deploy fabWeb into the Web subnet.
What should you do?

A.
Modify the service definition(csdef) for the cloud service.

B.
Run the Set-AzureSubnet PowerShell cmdlet.

C.
Run the Set-AzureVNetConfig PowerShell cmdlet.

D.
Modify the network configuration file.

E.
Modify the service configuration (cscfg) for the fabWeb web role.

Explanation:
Azure Service Definition Schema (.csdef File)
The service definition file defines the service model for an application. The file contains the definitions for the
roles that are available to a cloud service, specifies the service endpoints, and establishes configuration
settings for the service.
https://blog.vbmagic.net/2014/03/31/connecting-an-azure-web-role-to-an-existing-virtual-networkconnected-to-company-wan/