If u go for BS then u have to give it time ..I don't think so u will be able to study for Css along with it...BA is easily managable nd u will get to know about other subjects as well like pakistan studies and Islamiat along with it u can take one subect of ur interest other being english elective as u want to learn English...Other subject should b selected wisely nd u should go for the same subject in css exam too...BS takes four years although u will learn English in it but u won,t be able to prepair for css along with it...