A company wants to deploy a web-based application onto Azure. The application is going to be hosted on a set of Azure virtual machines located in different regions. They want to implement a strategy of Blue-Green deployment for all future application updates. You also want to implement an Azure DNS load balancing solution for implementing Blue-Green deployments. 
Which of the following would they use as the service for implementing Azure DNS load balancing?

Answer options:

A.Azure Standard Load Balancer
B.Azure CDN
C.Azure Traffic Manager
D.Azure Basic Load Balancer

Answer – C 
Azure Traffic Manager is Azure’s DNS based load balancing solution. 
There is a blog article also related to this. 

The other options are incorrect since they don’t have features of DNS routing. 
For more information on the article itself, please refer to the following link- 

https://azure.microsoft.com/en-in/blog/blue-green-deployments-using-azure-traffic-manager