(a)the gross total income consists only of investment income or income by way of long-term capital gains or both, no deduction shall be allowed to the assessee [under Chapter VI-A and nothing contained in the provisions of the second proviso to section 48 shall apply to income chargeable under the head "Capital gains"] [ Substituted by Act 12 of 1992, Section 57, for " under sub-Section (2) of section 48 or under Chapter VI-A" (w.e.f. 1.4.1993).];