Computer categories: A _____-purpose computer is engineered and optimized to perform one specific application or a narrowly defined set of tasks.

Introduction / Context:
Computers can be categorized by purpose (general vs special) and by signal type (digital, analog, hybrid). Understanding these distinctions clarifies design trade-offs and deployment contexts in embedded systems, industrial control, and consumer devices.

Given Data / Assumptions:

• We are focusing on “purpose” rather than signal processing type.
• Special-purpose machines are tailored to one application domain.
• General-purpose machines handle many tasks via software.

Concept / Approach:
A special-purpose computer is built for a dedicated function (e.g., router firmware platforms, automotive engine controllers, digital signage players). By contrast, analog/digital/hybrid refer to how data is represented and processed. Therefore, “special” completes the phrase correctly when describing a device designed for one specific application.

Step-by-Step Solution:

Verification / Alternative check:
Computer architecture references use “special-purpose” to describe dedicated systems; the alternatives describe other classification axes.

Why Other Options Are Wrong:

• Analog/digital/hybrid: classify computation style, not purpose.
• None of the above: incorrect because “special” is correct.

Common Pitfalls:
Mixing classification dimensions (purpose vs signal type) leading to incorrect matches.

Final Answer:
special