A Psychologist Wishes to Determine Whether Short-Term Memory Scores Are

A psychologist wishes to determine whether short-term memory scores are affected by the type of medication in hyperactive children. Sixty hyperactive children (30 boys and 30 girls) were randomly assigned to receive either Cylert or Ritalin (two kinds of amphetamines that are central nervous system stimulants) . Their short-term memory was tested on a 20-point scale (where 0 = no memory and 20 = perfect memory) . $\begin{array} { c c c c c c } \hline & \text { Boys } & && { \text { Girls } } \\\hline \text { Cylert } & \text { Placebo } & \text { Ritalin } & \text { Cylert } & \text { Placebo } & \text { Ritalin } \\\hline 12 & 5 & 3 & 5 & 4 & 12 \\10 & 6 & 2 & 6 & 6 & 9 \\13 & 7 & 5 & 2 & 7 & 14 \\10 & 6 & 6 & 4 & 6 & 13 \\9 & 4 & 1 & 3 & 5 & 9 \\12 & 5 & 4 & 2 & 4 & 12 \\13 & 6 & 2 & 4 & 5 & 8 \\10 & 7 & 6 & 6 & 6 & 15 \\11 & 5 & 1 & 2 & 7 & 12 \\12 & 7 & 5 & 4 & 7 & 11 \\\hline\end{array}$
-When comparing boys and girls in the interaction, which of the following is true?

A) boys do better on Cylert and girls do better on Ritalin
B) boys do better on Ritalin and girls do better on Cylert
C) there is a significant difference in short-term memory between girls on Cylert and boys on Ritalin
D) none of the above