Let X Be Normally Distributed with Mean μ and Standard

Multiple Choice

Let X be normally distributed with mean μ and standard deviation σ > 0. Which of the following is true about the z value corresponding to a given x value?

A) A positive z = (x - μ) /σ indicates how many standard deviations x is above μ.
B) A negative z = (x - μ) /σ indicates how many standard deviations x is below μ.
C) The z value corresponding to x = μ is zero.
D) All of the above.