Tax deduction basis clarified to gross income before deductions for amounts subject to withholding and included in total income. The amendment to Section 209 clarifies that tax is to be deducted on income 'as computed before allowing any deductions admissible under this Act' and only on income on which tax is required to be deducted under the relevant sections and which has been taken into account in computing total income; additionally, clause (c) is amended to add a cross reference to sub section (3A) after sub section (3).