A Buyer for a Manufacturing Plant Suspects That His Primary

A buyer for a manufacturing plant suspects that his primary supplier of raw materials is overcharging. In order to determine if his suspicion is correct, he contacts a second supplier and
Asks for the prices on various identical materials. He wants to compare these prices with those of
His primary supplier. He collected data on 6 different materials from both suppliers. He believes
That the differences are normally distributed. Which of the following tests will be the most
Appropriate?

A) Pooled-variance t test.
B) Paired t test.
C) Wilcoxon rank sum test.
D) Kruskal-Wallis rank Test.