Which of these is another form of the cumulative sum value plotted on the cumulative sum chart?

• A. \(C_i=(x_i-μ)+\sum_{j=1}^{i-1} (x_j+μ)\)
• B. \(C_i=(x_i-μ)+C_{i-1}\)
• C. \(C_i=(x_i-μ)+\sum_{j=1}^{i-1} (x_j+2μ)\)
• D. \(C_i=(x_i-μ)-C_{i-1}\)