How is the approval handled if a bequest is made to two out of three co-heirs?

Primary text

If the testator bequeaths the slave to two of the three sons, the third son has the option to approve the bequest to both of them, reject it entirely, or approve only a part of their bequest. He may approve equally or unequally, or approve the entirety for one and part for the other, or approve the entirety for one and part for the other. All these arrangements are valid because the right belongs to him, and he may act as he wishes concerning his right.