Bill is making a scale model of Willis Tower. The Willis Tower is $440\text{m}$ tall and his model is $110\text{cm}$ tall. What is the scale of the model, in its simplest form? 
选项为:A:$1:4$  B:$4:1$  C:$1:400$  D:$400:1$  请回答其中一个选项.