The given answer is correct. Just want to talk about option A here. What option "A" means is that, if your data is not normally distributed (the bell curve), where data is mostly scattered around the mean value, your cp/cpk or pp/ppk values will be affected (lower than 1.33). You will only get a higher process capability study values ( greater than 1.33) if you have less variation in your process, lesser the variation, the peak or nose of your data distribution is going to be much thinner and longer around the mean. Therefore, the shape of your data distribution will definitely have an effect on your cp/cpk or pp/ppk value. The more your data is spread, the lower process capability values will be calculated.