What should you do?

You are developing an ASP.NET MVC application that provides instant messaging capabilities to customers.
You have the following requirements:
. Messages must be able to be sent and received simultaneously.
. Latency and unnecessary header data must be eliminated.
. The application must comply with HTML5 standards.
You need to design the application to meet the requirements.
What should you do?
A. Configure polling from the browser.
B. Implement long-running HTTP requests.
C. Implement WebSockets protocol on the client and the server.
D. Instantiate a MessageChannel object on the client.