Concept:An error of commission occurs when a transaction is recorded in the wrong account of the same class or category.Explanation:The amount received from Koffi should be credited to Koffi's personal account.Instead, it was credited to Kofigo's personal account.Both Koffi and Kofigo are customers, so both accounts belong to the same class of accounts receivable.Since the mistake is within the same category and not between different types of accounts, it is not an error of principle.This is therefore an error of commission.Answer:B. commission