Katie bought three identical pencils, two identical pens and two identical erasers, and paid ＄$$11.60$$. Hannah bought one pencil, two pens and two erasers, and she paid ＄$$8.40$$. How much does one pencil cost? 
选项为:A:＄$$1.20$$  B:＄$$1.50$$  C:＄$$1.60$$  D:＄$$3.20$$  请回答其中一个选项.