$13.$ The debit side of a trial balance totals $$800$ more than the credit side. Which one of the following errors would fully account for the difference?

A $$400$ paid for plant maintenance has been correctly entered in the cash book and credited to the plant asset account.

B Discount received $$400$ has been debited to discount allowed account.

C A receipt of $$800$ for commission receivable has been omitted from the records.

D The petty cash balance of $$800$ has been omitted from the trial balance.

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