Alternate minimum tax applicability: adjusted total income deemed taxable when regular tax is lower, with mandatory accountant certification. Where a person other than a company has regular tax lower than the alternate minimum tax, the adjusted total income shall be deemed to be that person's total income and taxed at the prescribed rate; adjusted total income equals total income before giving effect to this Chapter increased by Chapter VI-A deductions (other than section 80P) and any deduction under section 10AA. Every applicable person must obtain and furnish an accountant's report, in the prescribed form, certifying computation of adjusted total income and alternate minimum tax by the due date for filing the return under section 139(1).