Suppose a Researcher Assessed Attitudes Towards a Certain Brand of Soda

Multiple Choice

Suppose a researcher assessed attitudes towards a certain brand of soda before and after conducting a taste test and noted the following results: $\begin{array}{ll}\text { Pre } & \text { Post } \\5 & 7 \\4 & 9 \\3 & 4 \\5 & 10 \\4 & 4 \\5 & 4\end{array}$ What is the mean difference?

A) -2
B) -12
C) 12
D) 6