The Following Six Months of Data Were Collected on Kelowna

Multiple Choice

The following six months of data were collected on Kelowna Company's electricity cost and the number of machine hours in a factory.
$\begin{array}{lrr}& \text { Electricity } & \text { Machine } \\\text { Month } & \text { cost } & \text { hours }\\\text { June } & \$ 25,160 & 4,500 \\\text { July } & 26,170 & 4,810 \\\text { August } & 27,250 & 5,120 \\\text { September } & 26,680 & 5,010 \\\text { October } & 27,950 & 5,430 \\\text { November } & 27,500 & 5,190\end{array}$
-Refer to the Figure.Which of the following is an independent-variable value used to calculate the cost line when using the high-low method?

A) $4,000
B) $5,430
C) $25,160
D) $27,950