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:

Identify the response variable used in this experiment.

A) The three display levels used by the supermarket.
B) The three price levels used by the supermarket.
C) The nine combinations of price level and display level used by the supermarket.
D) The weekly sales collected for each of the weeks.