A company has created a virtual network and also launched a set of virtual machines in the virtual network. They want to change the way the traffic is routed in the virtual network. Which of the following could be used to fulfil this requirement?

Answer options:

A.User Defined Routes
B.Application Security Groups
C.Network Security Groups
D.Azure DDoS Protection

Answer – A 
You can create your network routes using User Defined Routes 
The Microsoft documentation mentions the following 

Options B and C are incorrect since these are used to filter network traffic into and out of virtual networks. 
Option D is incorrect since this is used to protect infrastructure against DDoS attacks 
For more information on virtual network routing, please visit the below URL 

https://docs.microsoft.com/en-us/azure/virtual-network/virtual-networks-udr-overview