A $$16$$-quart radiator is filled with water.Four quarts are removed and replaced with pure antifreeze liquid.Then four quarts of the mixture are removed and replaced with pure antifreeze.This is done a third and a fourth time.The fractional part of the final mixture that is water is． 
选项为:A:$$\frac{81}{256}$$  B:$$\frac{27}{64}$$  C:$$\frac{37}{64}$$  D:$$\frac{175}{256}$$  请回答其中一个选项.