Increase in Trade Receivables via T-Account Balance Steps:

• Opening receivables: $15,000.
• Add credit sales: $15,000 +$85,000 = $100,000.
• Subtract cash received: $100,000 -$65,000 = $35,000.
• Subtract irrecoverable debts: $35,000 -$2,000 = $33,000 (closing balance).
• Increase: $33,000 -$15,000 = $18,000.

Why A is correct:

• Increase equals closing receivables minus opening, using formula: closing = opening + credit sales - cash received - irrecoverable debts.

Why the others are wrong:

• B: Ignores irrecoverable debts subtraction ($20,000 too high).
• C: Shows closing balance, not the increase from opening.
• D: Adds credit sales to opening without subtractions ($27,000 too high).

Final answer: A