Ten Healthy Adult Subjects Were Asked to Walk on a Treadmill

Ten healthy adult subjects were asked to walk on a treadmill while connected to monitors. One of two kinds of disturbances was applied during the walk, and the number of steps until adaptation was recorded. Each subject experienced both kinds of disturbance, in random order. Here are the data for these 10 subjects:
?
?
$$\begin{array} { | l | l | } \hline \text { Disturbance A } & \text { Disturbance B } \\\hline 11.5 & 4.5 \\\hline 8.3 & 3.4 \\\hline 7.4 & 5.5 \\\hline 5.4 & 3.3 \\\hline 8.2 & 7.2 \\\hline 8.8 & 4.7 \\\hline 4.5 & 4.1 \\\hline 6.8 & 9.4 \\\hline 7.5 & 5.2 \\\hline 4.8 & 4.4 \\\hline\end{array}$$ A test is conducted to test whether there is significant evidence of a different mean adaptation time (in steps) for the two disturbances. What is the test statistic for the appropriate test of hypothesis?

A) z = 2.42
B) t = 2.42
C) t = 2.53
D) F = 13.41