18. The cost of the machinery is $100,000. The tax written down value of the machinery is $19,500 when it is sold for $30,000. The necessary tax adjustment in respect of the sale of the machinery is: (A)A balancing charge of $10,500 (B) A balancing allowance of $19,500 (C) A balancing allowance of $70,000 (D) No balancing allowance and charge