System buses classification: Evaluate the statement: “The PCI bus is an external bus for personal computers.” Decide whether this characterization is accurate.

Introduction / Context:
Computer buses are often categorized as internal (on the motherboard/backplane) versus external (user-accessible peripheral interconnects like USB or Thunderbolt). The Peripheral Component Interconnect (PCI) standard revolutionized internal expansion during the 1990s. This question asks whether PCI is an “external” bus.

Given Data / Assumptions:

• PCI is a motherboard expansion bus for add-in cards.
• External buses typically refer to self-powered ports or cables exposed outside the chassis.
• PCI slots are inside the PC case, not externally accessible during normal use.

Concept / Approach:
Classify PCI according to location and usage. Internal buses connect components on the board or backplane; external buses connect devices via cables outside the chassis. PCI is therefore internal, even though it connects to peripherals via add-in cards.

Step-by-Step Solution:

Verification / Alternative check:
Motherboard manuals and standards documents place PCI firmly as an internal bus; external connectivity may be provided by cards that use PCI internally.

Why Other Options Are Wrong:

Common Pitfalls:
Equating “external devices” with “external bus”; confusing expansion capability with physical externality.

Final Answer:
Incorrect