The correct option is A On the debit side of Profit & Loss A/c
Profit and loss account records the indirect expenses and incomes which is not the main purpose of the business. Expenses are debited and incomes are credited to the profit and loss account. Discount allowed is the part of income which is sacrificed by the firm. It is the incentive given to the debtors for early payments. Since it is a reduction in the revenue of the year, it is shown on the debit side of the profit and loss account