A network engineer is redesigning a company's QoS solution. The company is currently using IP Precedence, but the engineer plans to move to DiffServ. It is impo...

A network engineer is redesigning a company's QoS solution. The company is currently using IP Precedence, but the engineer plans to move to DiffServ. It is important that the new solution provide backward compatibility with the current solution. Which technology should the design include?

A. expedited forwarding B. assured forwarding C. class selector code points D. default per-hop behavior