The Following Information Is Available for a Company's Cost of Sales

The following information is available for a company's cost of sales over the last five months.
$\begin{array} { | l | l | l | } \hline \text { Month } & \text { Units sold } & \text { Cost of sales } \\\hline \text { January } & 400 & 31,00 \\\hline \text { February } & 800 & 37,000 \\\hline \text { March } & 1,600 & 49,000 \\\hline \text { April } & 2,400 & 61,000 \\\hline\end{array}$
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Using the high-low method, the estimated total fixed cost is:

A) $100,000.
B) $13,692.
C) $25,000.
D) $50,000.
E) $30,000.