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In the following pairs of OSI protocol layer/sub-layer and its functionality, the INCORRECT pair is

1. Network layer and Routing
2. Data Link Layer and Bit synchronization
3. Transport layer and End-to-end process communication
4. Medium Access Control sub-layer and Channel sharing

(a) One of the main functionality of Network Layer is Routing. So, option (a) is CORRECT.
(b) Bit Synchronization is always handled by Physical Layer of OSI model but not Data Link
Layer.

So, option (b) is INCORRECT.
(c) End – to – End Process Communication is handled by Transport Layer. So, option (c) is
CORRECT.
(d) MAC sub layer have $3$ types of protocols (Random, Controlled and Channelized Access).

So, option B is incorrect pair.

edited

Because, Data Link Layer is associated with Frame Synchronization, and not Bit Synchronization.

Option B

Data Link Layer and Bit synchronization

In data link layer framing is counted and syn it count bit by HCDL protocol wgich is out of syllabus.
1) Yes, Network layer does Rotuing
2) No, Bit synchronization is provided by Physical Layer
3) Yes, Transport layer provides End-to-end process
communication
4) Yes, Medium Access Control sub-layer of Data Link Layer provides
Channel sharing. 
Options B is right because bit synchronisation is done in physical layer
B option