You have business services that run on an on-premises mainframe server.
You must provide an intermediary configuration to support existing business services and Azure. The business
services cannot be rewritten. The business services are not exposed externally.
You need to recommend an approach for accessing the business services.What should you recommend?

A.
Connect to the on-premises server by using a custom service in Azure.

B.
Expose the business services to the Azure Service Bus by using a custom service that uses relay binding.

C.
Expose the business services externally.

D.
Move all business service functionality to Azure.

Explanation:
The Service Bus relay service enables you to build hybrid applications that run in both an Azure datacenter and
your own on-premises enterprise environment. The Service Bus relay facilitates this by enabling you to securely
expose Windows Communication Foundation (WCF) services that reside within a corporate enterprise network
to the public cloud, without having to open a firewall connection, or require intrusive changes to a corporate
network infrastructure.
http://azure.microsoft.com/en-gb/documentation/articles/service-bus-dotnet-how-to-use-relay/