Participants Rated Their Mood Score Out of 20 Before and After

Multiple Choice

Participants rated their mood score out of 20 before and after listening to Reign in Blood by the thrash metal band Slayer. $\begin{array} { | c | c | } \hline \text { Before Listening to Slayer } & \text { After Listening to } \mathbf { S l a y e r } \\\hline 5 & 14 \\\hline \mathbf { 8 } & \mathbf { 5 } \\\hline \mathbf { 9 } & 17 \\\hline 4 & 18 \\\hline \mathbf { 3 } & \mathbf { 8 } \\\hline 15 & 19 \\\hline 12 & 14 \\\hline \mathbf { 6 } & 16 \\\hline\end{array}$
-What are the degrees of freedom for this study?

A) 7
B) 8
C) 16
D) 15