How can a technician verify the accuracy of the air pressure gauge?

Answer: B — By comparing it with a calibrated pressure gauge

Verifying the accuracy of an air pressure gauge by comparing it with a calibrated pressure gauge is a standardized and reliable method. Calibration ensures that the gauge in question provides readings that are aligned with a reference standard, which is essential for accurate diagnostics and maintenance. A calibrated gauge has been tested and adjusted to ensure it measures accurately within a predetermined range, thereby serving as a trustworthy benchmark. This method allows the technician to identify any discrepancies in the readings between the two gauges. If the readings do not match, the technician can then determine whether the original gauge is functioning correctly or needs recalibration or replacement. This direct comparison provides a clear and quantifiable way to assess gauge performance. Other methods, such as visual estimation or manual adjustments, lack the precision required for accurate diagnostics, while a physical inspection of gauge components may reveal mechanical issues but does not directly confirm the gauge's accuracy in measuring pressure.