The correct answer is: D. in no case later than the date of redemption.
Debentures are a type of loan that a company can issue to raise money. The discount on issue of debentures is the difference between the face value of the debentures and the price at which they are issued. This discount is amortized over the life of the debentures and is written off against the profit and loss account in each accounting period.
The discount on issue of debentures must be written off in no case later than the date of redemption. This is because the discount represents a loss to the company and it must be recognized in the financial statements as soon as possible.
Option A is incorrect because the discount on issue of debentures is not written off before redemption. The discount is amortized over the life of the debentures and is written off against the profit and loss account in each accounting period.
Option B is incorrect because the discount on issue of debentures is not written off after redemption. The discount is amortized over the life of the debentures and is written off against the profit and loss account in each accounting period.
Option C is incorrect because the company cannot decide when to write off the discount on issue of debentures. The discount must be written off in no case later than the date of redemption.