For the Cp of two normally distributed processes $($Process M and Process N$)$ to be identical, we must have:

Group of answer choices

a$.$ Different spec. limits for both Processes M & N$.$

b$.$ Different Cpk values for both Processes M & N$.$

c$.$ Both a$,$ and b$.$

d$.$ Identical variance in control limits for both Processes M & N$.$

e$.$ Identical specification limits for both Processes M & N$.$

f$.$ Both d$,$ and e$.$