The Deed of Donation by a in Favor of B

The deed of donation by A in favor of B states: "Donation Inter Vivos" but there is a provision that although the land donated shall be delivered to the donee immediately upon perfection of the same with right to enjoy the fruits of the land, it will pass to the donee after the death of the donor. After the donor's death, the heirs sought to recover the property. Will the action prosper?

A) No, because since the donation is a inter vivos, it took effect driving the lifetime of the donor.
B) No, because the donee has acquired ownership over the property.
C) Yes, because the donation is a donation mortis causa hence, it has to comply with the formalities of a will and since it did not, it is void. (Art. 728, NCC)
D) No, because a donation inter vivos is irrevocable.