Choose the correct answer below. a. a z-score is an area under the normal curve. b. a z-score is a conversion that standardizes any value from a normal distribution to a standard normal distribution. c. if values are converted to standard z-scores, then procedures for working with all normal distributions are the same as those for the standard normal distribution. d. the area in any normal distribution bounded by some score x is the same as the area bounded by the equivalent z-score in the standard normal distribution.