Nonbusiness deductions of taxpayers other than corporations

In the case of a taxpayer other than a corporation, the deductions allowable by this chapter which are not attributable to a taxpayer’s trade or business shall be allowed only to the extent of the amount of the gross income not derived from such trade or business. For purposes of the preceding sentence—

(A) any gain or loss from the sale or other disposition of— (i) property, used in the trade or business, of a character which is subject to the allowance for depreciation provided in section 167, or (ii) real property used in the trade or business, shall be treated as attributable to the trade or business;

(B) the modifications specified in paragraphs (1), (2)(B), and (3) shall be taken into account;

(C) any deduction for casualty or theft losses allowable under paragraph (2) or (3) of section 165(c) shall be treated as attributable to the trade or business; and

(D) any deduction allowed under section 404 to the extent attributable to contributions which are made on behalf of an individual who is an employee within the meaning of section 401(c)(1) shall not be treated as attributable to the trade or business of such individual.