Ruth Executes a Will Naming Her Nephew Stan as Sole

Ruth executes a will naming her nephew Stan as sole beneficiary. One year later, Ruth executes another will, naming her niece Tammy as sole beneficiary, but does not state that she is revoking the previous will. On Ruth's death

A) Stan and Tammy will share the estate in equal shares.
B) Stan will be the sole heir.
C) Tammy will be the sole heir.
D) the estate will pass as if there were no will.