An Analyst Has a Set of Normally Distributed Intervally Scaled

Multiple Choice

An analyst has a set of normally distributed intervally scaled data resulting from two observations on the same sample of subjects,and he wishes to investigate if there is any difference in these two means.The appropriate statistical procedure is

A) z-test for difference in two means.
B) Analysis of variance.
C) Paired sample t-test.
D) Chi-square goodness-of-fit test.
E) Regression analysis.