The distribution of certain test scores is a nonstandard normal distribution with a mean of 50 and a standard deviation of 6. What are the values of the mean and standard deviation after X - H all test scores have been standardized by converting them to z-scores using z = ? O A. The mean is 100 and the standard deviation is 10. O B. The mean is 0 and the standard deviation is 1. O C. The mean is 10 and the standard deviation is 100. O D. The mean is 1 and the standard deviation is 0