The question was: The post-treatment scores for the placebo (control) group
Your Answer: Are leptokurtic
Answer and explanation: Your answer is incorrect. The correct answer is Have a negative skew.
The histogram of the post-treatment scores for the control group has more scores on the right, or positive,
end of the graph and fewer scores on the left, or negative, end of the graph. The distribution then "points"
towards the negative end giving the scores a negative skew. Leptokurtic refers to the size of a distribution's
tails. A leptokurtic histogram would have tails which are thick.