A Corporation, Which Began Business on January 1, 2006, Appropriately

A corporation, which began business on January 1, 2006, appropriately uses the instalment sales method of reporting for accounting purposes. The following data were available for the years 2006 and 2007: $\begin{array}{|l|l|l|}\hline & \mathbf{2 0 0 6} & \mathbf{2 0 0 7} \\\hline \text { Instalment sales } & \$ 1,050 & \$ 1,260 \\\hline \text { Cost of instalment sales } & 840 & 945 \\\hline \text { General and administrative expenses } & 105 & 126 \\\hline \text { Cash collected on } 2006 \text { instalment sales } &450 & 375 \\\hline \text { Cash collected on } 2007 \text { instalment sales } & & 600 \\\hline\end{array}$ The balance in the deferred gross profit control account on December 2007 should be:

A) $159
B) $210
C) $315
D) $525