The Probability Distribution of All Possible Values of the Sample $\bar { x }$

The probability distribution of all possible values of the sample mean $\bar { x }$ is

A) the probability density function of $\bar { x }$ .
B) the sampling distribution of $\bar { x }$ .
C) the grand mean, since it considers all possible values of the sample mean.
D) one, since it considers all possible values of the sample mean.