The correct answer is: C. a communications processor.
A communications processor is a device that assembles groups of characters into complete messages prior to their entering the CPU. It is responsible for converting data into a format that can be transmitted over a communication channel, and for receiving and decoding data that is transmitted over a communication channel.
A compiler is a program that translates a program written in a high-level language into a low-level language, such as machine code. An interpreter is a program that executes a program written in a high-level language directly, without translating it into a low-level language. An editor is a program that allows users to create and modify text files.
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