In instrumentation, which of the following best describes resolution?

• A. The range of measurements the instrument can display.
• B. The speed of response to a change.
• C. The calibration stability over time.
• D. The fineness of detail or the smallest increment of change an instrument can detect.

Answer: (D)

Resolution in instrumentation is about how finely the instrument can distinguish small changes in the measured quantity—the smallest increment of change it can detect. That describes the fineness of detail or the smallest step the instrument can resolve, which is why this choice is best. The range describes how large values the instrument can display, not how finely it can differentiate small differences. The speed of response refers to how fast the instrument responds to changes, and calibration stability concerns drift in accuracy over time. For example, a thermometer that updates in 0.1 °C steps has a resolution of 0.1 °C, meaning it can distinguish temperature changes at that increment level (assuming noise doesn’t mask smaller changes).