Which of these is a reason, why the Cusum charts are better than the Shewhart control charts?

• A. Because they are having information about only one sample
• B. Because the quantity plotted on the Shewhart control charts is variable
• C. Because the quantity plotted on the Cusum chart contains information about more than one sample
• D. Because the quantity plotted on the Cusum control charts is containing information about a single sample