John is a newly minted quality engineer at MakeStuff Inc. His boss tells him to increase the process capability index of their main product. John is somewhat lazy and does not want to tackle the variation in the process, so he decides to simply increase the upper specification limit and reduce the lower specification limit. Does this increase the process capability index? 

a. No, it does not, because the variation in the process stays unchanged. 

b. Yes, it does, though one might question if the underlying process is really better. 

c. That depends on many other variables, including the control limits. 

d. No, the process capability index would only change if the control limits were changed.