Data Set 10-1: a College Teacher Was Assigned 4 Freshmen $$\begin{array} { c c } 2006 & 2010 \\\hline 26 & 15 \\22 & 23 \\17 & 14 \\15 & 10\end{array}$$

Multiple Choice

Data Set 10-1: A college teacher was assigned 4 freshmen advisees. He administered an attitude scale that measured liberalism-conservatism. Four years later, just before graduation, all 4 took the same scale again. High scores indicate conservative attitude. The following scores were obtained.
$$\begin{array} { c c } 2006 & 2010 \\\hline 26 & 15 \\22 & 23 \\17 & 14 \\15 & 10\end{array}$$
-A t test of Data Set 10-1 would result in a t value of

A) 1.60
B) 0.90
C) 0.61
D) 1.80