You are the network administrator of an enterprise with a main site and multiple remote sites. Your network carries both VOIP and data traffic. You agree with your service provider to classify VOIP and data traffic according to the different service RFCs. How can your data and VOIP traffic be marked？（）

• A、data marked with DSCP AF21，VOIP marked with DSCP EF
• B、data marked with DSCP AF51，VOIP marked with DSCP EF
• C、data marked with the DE-bit，VOIP marked with the CLP-bit
• D、data marked with DSCP EF，VOIP marked with DSCP AF31
• E、data marked with IP precedence 5 VOIP marked with DSCP EF