Following Is a List of Account Balances (Except for Owner's

Following is a list of account balances (except for owner's equity) of Wilson Mowing as of December 31 of the first year of operation:
$$\begin{array} { | l | r | } \hline \text { Accounts receivable } & \$ 2,500 \\\hline \text { Accounts payable } & 3,500 \\\hline \text { Salary expense } & 4,500 \\\hline \text { Repairs expense } & 800 \\\hline \text { Truck } & 8,500 \\\hline \text { Equipment } & 6,300 \\\hline \text { Notes payable } & 8,200 \\\hline \text { Cash } & 6,800 \\\hline \text { Supplies expense } & 1,600 \\\hline \text { Service revenue } & 31,900 \\\hline \text { Gasoline expense } & 3,800 \\\hline \text { Salary payable } & 200 \\\hline\end{array}$$ The sole proprietor, J.D. Wilson, contributed $3,000 at the beginning of the year and made withdrawals of $12,000 during the year.
At the end of the year, what is the amount of total assets?

A) $12,200
B) $24,100
C) $11,900
D) $21,200