Which of the following commonly used conversion factors cannot be used to convert weight units? 
选项为:A:$\frac{1000\text{g}}{1\text{kg}}$  B:$\frac{16\text{ounces}}{1\text{lb}}$  C:$\frac{1\text{kg}}{1000\text{g}}$  D:$\frac{60\text{minutes}}{1\text{day}}$  请回答其中一个选项.