What describes 'buses' in a computer system?

In the context of computer systems, 'buses' refer to a collection of circuits that facilitate the transfer of data between different components of the system, such as the CPU, memory, and input/output devices. Buses serve as communication pathways, ensuring that data is transmitted accurately and efficiently across the various hardware components.

This concept is integral to understanding how data flows within a computer, as buses can vary in width (measured in bits) and function, affecting the overall speed and capability of data handling in the system. Given their critical role in data transfer, identifying buses strictly as circuits dedicated to this purpose is an accurate and straightforward description.

The other options, while relevant to computer systems, do not describe buses. For instance, data encryption pertains to security measures, computer memory refers to storage locations, and hardware components for graphic rendering relate to the graphical processing unit. Thus, only the description of buses as a collection of circuits for data transfer captures their essence within a computer system.