(a) When a testator has attempted to make a testamentary gift of property that is not the testator's own and has also given a benefit to a person to whom the property belongs, the person shall elect to take either under the will or against the will.

(b) An election pursuant to subsection (a) of this Code section shall not be required if:

(1) The will itself, from other causes, is not effective in passing title to the property in question;

(2) The testator has an interest in the property in question upon which the will may operate;

(3) The testamentary gift shows that the testator intended to give the property only in the event that the testator's own title was good; or

(4) The benefit given to the person called upon to elect is not from the testator's own property but is by virtue of a power of appointment in the testator.