Has a shaded dial that when used with a mirror the operator will always get a correct reading.

• A. Dial caliper
• B. Last word indicator
• C. Vernier caliper
• D. Magnetic base

Answer: (B)

Reading the smallest increment on an analog dial can be ruined by parallax, the tendency to misread when your eye isn’t perfectly in line with the scale. A shaded dial with a mirror is designed to eliminate that problem by improving contrast and giving a reflected view that lets you align the pointer with the scale from a consistent line of sight. The device that uses this setup is intended to show the final, most precise reading—the last word—reliably, no matter the viewing angle.

That’s why this option is the best choice: it’s built to minimize reading errors by using shading and a mirror to present the measurement in a way that makes the last digit unambiguous. A dial caliper and a Vernier caliper rely on their own scale-reading methods rather than a shaded dial plus mirror approach, and a magnetic base is just a stand, not a reading device.