Which one of the following correctly states a purpose of the generation-skipping transfer tax (GSTT)? A) To encourage the transfer of wealth to younger generations B) To ensure transfer taxes are paid at each generation by transfer taxing wealth when it is transferred to a skip person C) To discourage generation-skipping transfers by using up the transferor's gift or estate tax credit amounts more quickly D) To substitute the GSTT for any gift or estate tax due on the transfer instead of imposing the gift or estate tax