-On Which of the Following Tests Did Sarah Perform Best

$$\begin{array} { | l | l | } \hline \boldsymbol { X } & \boldsymbol { f } \\\hline & \\\hline 17 & 2 \\\hline 16 & 4 \\\hline 15 & 5 \\\hline 14 & 7 \\\hline 13 & 7 \\\hline 12 & 8 \\\hline 11 & 10 \\\hline 10 & 9 \\\hline 9 & 5 \\\hline 8 & 3 \\\hline\end{array}$$
-On which of the following tests did Sarah perform best?
$$\begin{array} { | l | l | l | l | l | } \hline \text { Test } & \text { A. } & \text { B. } & \text { C. } & \text { D. } \\\hline \text { mean } & 40 & 80 & 30 & 70 \\\hline \text { s.d. } & 10 & 20 & 4 & 15 \\\hline & & & & \\\hline \text { Sarah } & 60 & 60 & 32 & 70 \\\hline\end{array}$$