Resident co-operative society tax regime allows concessional income tax with restricted deductions and mandatory option conditions. Special tax regime for a resident co-operative society allows income-tax to be paid at 22% for a tax year, at the society's option, on total income computed without specified deductions and without set-off of carried-forward loss or depreciation attributable to those deductions. The option is available only if exercised in the prescribed manner on or before the due date for filing the return of income, and once exercised it applies to subsequent tax years unless the conditions cease to be satisfied. Failure to satisfy the statutory requirements makes the option invalid for that and later tax years.