(a)Where, before the 1st day of March, 1984, an assessee has incurred any expenditure (not being in the nature of capital expenditure incurred on the acquisition of any land or building or construction of any building) on scientific research undertaken under a programme approved in this behalf by the prescribed authority having regard to the social, economic and industrial needs of India, he shall, subject to the provisions of this sub-section, be allowed a deduction of a sum equal to one and one-fourth times the amount of the expenditure certified by the prescribed authority to have been so incurred during the previous year.