Answer:
b. sampling distribution of the mean.
Step-by-step explanation:
A random variable often used in statistics and probability, is a variable that has its possible values as numerical outcomes of a random experiment or phenomenon. It is usually denoted by a capital letter, such as X.
In statistics and probability, random variables are either continuous or discrete.
In Statistics, sampling can be defined as a process used to collect or select data (objects, observations, or individuals) from a larger statistical population using specific procedures.
The probability distribution of the sample mean is called the sampling distribution of the mean and it's a graph of the sampled data (mean).
Mathematically, sampling distribution of the mean is given by the formula;
uX = u.
Where, uX is the mean of the sampling distribution of the mean.
A hypothesis test in which rejection of the null hypothesis occurs for values of the point estimator in either tail of the sampling distribution is called a two-tailed test. Thus, it is two sided and is typically used to test whether a sample is less than or greater than a set of values.