The Table Below Shows the Quantity of Gold Bars (Q_b)in

The table below shows the quantity of gold bars (Q_b) in thousands,the extraction cost for each thousand bars (in millions of dollars) ,and the user cost of each thousand bars (in millions of dollars) facing the OZ Mining Company this year. $$\begin{array} { c c c } \begin{array} { c } \text { Quantity of Gold Bars } \\\text { (in thousands) }\\\hline\end{array} & \begin{array} { c } \text { Extraction Cost } \\\text { (in millions of dollars) }\\\hline\end{array} & \begin{array} { c } \text { User Cost } \\\text { (in millions of dollars) }\\\hline\end{array} \\0 & \$ 10 & \$ 5 \\1 & 15 & 5 \\2 & 20 & 5 \\3 & 25 & 5 \\4 & 30 & 5 \\5 & 35 & 5\end{array}$$ Refer to the data.If the current price of a bar of gold is $25,000,how many bars (in thousands) should OZ extract and sell this year in order to maximize profits?

A) 1.
B) 2.
C) 3.
D) 4.