Which type of Control Chart should be used to monitor the number of defects per unit?

The type of Control Chart best suited for monitoring the number of defects per unit is the Attribute Control Chart. Attribute Control Charts are specifically designed to handle data that can be counted, such as defects or non-conformities, rather than measured. These charts focus on the frequency of occurrences, which makes them ideal for situations where quality characteristics are assessed based on pass/fail criteria or counts, like defects.

In the context of process control, the Attribute Control Chart allows for the tracking of the number of defects over time and helps identify any variations that may affect the process. By utilizing this type of chart, organizations can easily visualize trends, determine if the process is in control, and make informed decisions regarding process improvements.

While other charts listed might serve different purposes, they do not focus on counting defects per unit in the same way. Variable Control Charts are intended for continuous data that can take on any value (measurement data), while Exponential and Continuous aren't standard classifications used specifically for counting items like defects. Hence, the Attribute Control Chart is the correct choice for monitoring defect counts effectively.