(iii)The term “property” includes an interest in property. (iv)A specific portion of property shall be treated as separate property. (v)An election under this paragraph with respect to any property shall be made by the executor on the return of tax imposed by section 2001. Such an election, once made, shall be irrevocable. (C)In the case of an annuity included in the gross estate of the decedent under section 2039 (or, in the case of an interest in an annuity arising under the community property laws of a State, included in the gross estate of the decedent under section 2033) where only the surviving spouse has the right to receive payments before the death of such surviving spouse— (i)the interest of such surviving spouse shall be treated as a qualifying income interest for life, and (ii)the executor shall be treated as having made an election under this subsection with respect to such annuity unless the executor otherwise elects on the return of tax imposed by section 2001.