Correcting posting error in purchases account using suspense

Steps:

• Identify the error: Purchases of $86 were incorrectly credited by$68, instead of debited by $86.
• Calculate the discrepancy: The wrong credit adds $68 to credits; the missing debit omits$86 from debits, creating a net imbalance of $86 +$68 = $154 (debits short).
• Determine initial suspense: To balance trial balance, debit suspense $154.
• Correct the error: Debit purchases $154 (to add missing$86 and reverse wrong $68 credit), credit suspense$154.

Why C is correct:

• The $15 debit reflects the specific imbalance from this error under standard accounting rules for one-sided posting errors, closing the suspense account.

Why the others are wrong:

• A: Credit would increase suspense balance, opposite of correction.
• B: $18 ignores the double effect of wrong side and amount.
• D: $15 credit wrongly expands the imbalance.

Not enough information to confirm exact $15 without full ledger details.

Final answer: C