For the Following Data, What Is the Standard Error of the Difference

Multiple Choice

For the following data, what is the standard error of the difference scores? $$\begin{array} { | r r } \hline { \text { Before } } & \text { After } \\\hline 160 & 153 \\\hline 125 & 124 \\\hline 142 & 136 \\\hline 187 & 167 \\\hline\end{array}$$

A) 8.10
B) 4.26
C) 4.05
D) 2.10