The Open Systems Interconnection (OSI) is a conceptual model whose purpose is to make networks more manageable. Its objectives i
nclude allowing for more portable hardware and software integration, the creation of standard interfaces that would allow manufacturers of different systems to interconnect their equipment and the creation of a model that would be used world-wide. There are seven layers to the OSI. The lowest - or first - layer allows a contiguous sequence of bits to be transmitted through the network. Which is the first layer: A. data-link layer, B. physical layer, C. network layer, D. transport layer