In the course of locating the reason for the difference in the trial balance, it has been found that an amount received from a customer has been debited to his account and a purchase from a supplier has been wrongly entered in the ledger as Rs.17,720 instead of Rs.17,270. These errors may be classified as_

• A. Errors of commission.
• B. Errors of omission.
• C. Errors of Principle.
• D. Both errors of commission and omission.