问题：

[多选] Which three MPLS statements are true？（）

A . Cisco Express Forwarding （CEF） must be enabled as a prerequisite to running MPLS on a Cisco router.
B . Frame-mode MPLS inserts a 32-bit label between the Layer 3 and Layer 4 headers.
C . MPLS is designed for use with frame-based Layer 2 encapsulation protocols such as Frame Relay， but is not supported by ATM because of ATM fixed-length cells.
D . OSPF， EIGRP， IS-IS， RIP， and BGP can be used in the control plane.
E . The control plane is responsible for forwarding packets.
F . The two major components of MPLS include the control plane and the data plane.