Which of the Following Is the Definition of the "Arithmetic

Which of the following is the definition of the "arithmetic mean"?

A) A statistical procedure that allows researchers to draw inferences about how statistically meaningful a study's results are.
B) A commonly used measure of variability that indicates the average difference between scores in a distribution and their mean.
C) An average that is calculated by adding up a set of quantities and dividing the sum by the total number of quantities in the set.
D) A statistical test that assesses how likely it is that a study's results occurred merely by chance so that the researcher knows that the probability that the difference is "real" is overwhelming.