Based on the Following Scenario:
a Researcher Wanted to Examine

Multiple Choice

based on the following scenario:
A researcher wanted to examine if soil type had any effects on the heights of daylilies. Ten bulbs of daylilies were planted in each of the three different types of soil. The thickness of the soil (X) was also measured for each pot. After three months, the heights of the plants (Y) were measured. Below are the group means of the study.
$\begin{array}{cccc}\hline \text { soil type } & n & \text { heights of daylilies (Y) } & \text { thickness of soil }(X) \\\hline 1 & 10 & \bar{Y}_{1}=20 & \bar{X}_{1}=21 \\2 & 10 & \bar{Y}_{2}=25 & \bar{X}_{2}=18 \\3 & 10 & \bar{Y}_{3}=30 & \bar{X}_{2}=15 \\\hline\end{array}$
-If there is a substantial, positive correlation between the thickness of soil (X) and the height of daylilies (Y) , which group will have the highest adjusted mean height?

A) Group 1 ( $\bar{Y}_{1}^{\prime}$ )
B) Group 2 ( $\bar{Y}_{2}^{\prime}$ )
C) Group 3 ( $\bar{Y}_{3}^{\prime}$ )
D) All groups would have the same adjusted mean.
E) Any of the above situation is possible.