Which four of these statements are restrictions for Frame Relay PVC bundles with QoS support for IP and MPLS？ （）

• A、A PVC bundle will not come up unless all the precedence， DSCP， and EXP levels are configured in thebundle.
• B、A PVC bundle can perform precedence and DSCP matching at the same time
• C、A PVC bundle may contain no more than sixteen PVCs
• D、A PVC can be in only one PVC bundle
• E、A PVC bundle cannot perform precedence and DSCP matching at the same time.
• F、A PVC bundle may contain no more than eight PVCs.