A Study Was Conducted to Test the Effectiveness of Supermarket

A study was conducted to test the effectiveness of supermarket sales strategies. At one supermarket, the price level (regular, reduced price, and at cost to supermarket) and display level
(normal display space, normal display space plus end-of-aisle display, and twice the normal
Display space) were tested to determine if they had any effect on the weekly sales of a particular
Supermarket product. Each of the combinations of price level and display level were put in place
For a randomly selected week and the weekly sales of the product was recorded. Each combination
Was used three times over the course of the experiment. The results of the study are shown here:

The ANOVA table is shown below:
$\begin{array}{l|c|c|c|c|c}\text { Source } & \mathrm{DF} & \mathrm{SS} & \mathrm{MS} & \mathrm{F} & \mathrm{P} \\\hline \text { Display } & 2 & 1691393 & 845696 & 1709.37 & 0.0000 \\\text { Price } & 2 & 3089054 & 154427 & 3121.89 & 0.0000 \\\text { Display }{ }^{*} \text { Price } & 4 & 510705 & 127676 & 258.07 & 0.0000 \\\text { Error } & 18 & 8905 & 495 & & \\\text { Total } & 26 & 5300057 & & &\end{array}$
Based on the results found in the ANOVA table, should the Main Effects tests for either Display or
Price be conducted?

A) No. The interaction of Display and Price indicates that the Main Effects should not be tested.
B) It depends on whether the main effects tests will be significant or not.
C) Yes. The main effects tests are both significant and should be tested.
D) Yes. The interaction of Display and Price indicates that the Main Effects should be tested.