Which of the following is NOT one of the four types of calibration?

The correct choice identifies one of the terms related to calibration activities. Calibration is typically categorized into recognized types that help ensure measurement devices or systems function accurately. Among these recognized types are full, partial, and specific other classifications that directly pertain to the calibration process.

The term 'inactive' does not align with any standard calibration type in established protocols. Similarly, 'not required' is not a recognized form of calibration; it implies that calibration may not be necessary under certain conditions but does not reflect a type of calibration itself. On the other hand, both 'full' and 'partial' refer to distinct types of calibration processes, where full calibration entails a comprehensive check and adjustment of all settings, and partial calibration addresses only specific aspects or parameters of the device.

Therefore, the selection that does not represent an established type of calibration fits appropriately with the context of the question.