A PCIe base expansion card can be characterized as which of the following?

The correct choice, which describes a PCIe base expansion card, is that it is a smaller circuit board. PCIe, or Peripheral Component Interconnect Express, is a high-speed interface standard designed to connect various hardware components to a computer's motherboard.

These expansion cards are typically designed to be inserted into a PCIe slot on a motherboard, allowing functional enhancements such as improved graphics, additional network capabilities, or extra storage options. They are distinctly different from a large motherboard, which is the main circuit board containing essential components like the CPU, RAM, and chipset.

Unlike a power supply unit that manages power distribution within the computer and a cooling system that helps regulate temperature, a PCIe base expansion card itself is primarily a smaller component that serves a specific function while relying on the motherboard for power and connectivity. Thus, the characterization of a PCIe expansion card as a smaller circuit board accurately reflects its design and purpose within a computer system.