Which of the following layers defines the mechanisms that allow data to be passed from one
network to another?

A.
Network layer

B.
Session layer

C.
Physical layer

D.
Data-link layer

Explanation:
The network layer defines the mechanisms that allow data to be passed from one network to
another.

Answer B is incorrect. The session layer is responsible for data synchronization between the
applications on the sending device and the receiving device.

Answer C is incorrect. The physical layer is the lowest layer of the OSI model. The physical layer is
responsible for packaging and transmitting data over physical media. This layer controls the way in
which data is sent and received over a physical medium.

Answer D is incorrect. The data-link layer is responsible for error free transfer of data frames.