A. Network layer
B. Physical layer
C. Transport layer
D. Application layer

A. Framing
B. Error control
C. Flow control
D. Channel coding

A. Logical link control sublayer
B. Media access control sublayer
C. Deals with transmission of data packets to and from the network-interface card, and also to and from another remotely shared channel. the mac sublayer also prevents collision using protocols like csma/cd.
D. Error control sublayer

A. Synchronization bytes
B. Addresses
C. Frame identifier
D. All of the mentioned

A. Logical link control sublayer
B. Media access control sublayer
C. Network interface control sublayer
D. Application access control sublayer

A. Random error
B. Burst error
C. Inverted error
D. Double error

A. Cyclic redundancy check
B. Code repeat check
C. Code redundancy check
D. Cyclic repeat check

A. Ethernet
B. Point to point protocol
C. Hdlc
D. All of the mentioned

A. Csma/cd
B. Csma/ca
C. Both csma/cd & csma/ca
D. Hdlc

A. Piggybacking
B. Cyclic redundancy check
C. Fletcher’s checksum
D. Parity check