WAN data link encapsulation types include which of the following? (Choose two)

A. T1
B. Frame Relay
C. DSL
D. PPP
E. ISDN
F. IPX

Answer: B, D

Explanation:
Frame relay and PPP is used with WAN encapsulation.
Frame Relay most closely compares to the OSI data link layer (Layer 2). If you remember
that the word "frame" describes the data link layer protocol data unit (PDU), it will be
easy to remember that Frame Relay relates to OSI Layer 2. Like other data-link protocols,
Frame Relay can be used to deliver packets (Layer 3 PDUs) between routers.