Section 24 of the Income Tax Act, 1961, deals with deductions from the "Net Annual Value" of a house property to arrive at the taxable income from that property. There are two main deductions allowed:
A standard deduction under Section 24(a) at a flat rate of 30% of the Net Annual Value.
A deduction for interest paid on borrowed capital for the property under Section 24(b).
30% is equivalent to the fraction 3/10. Therefore, the correct option is (c).