This is one of the valid questions that students of this age come across. The reasons being rising competition and myriads of career options available.
Nevertheless, there are ways which can help us resolve this dilemma effectively.
One is before you decide on a final career option, sit down with a paper pencil and jot down what careers are you interested in. Then read up more about these and the ones that are new to you. Know details like courses, rospectus, eligibility, benefits, disadvantages etc. A simple way to do this would be just log on to http://www.youngbuzz.com/careers/career-options
This is one-stop for all the career information.
Once you have done this you need to know more about yourself,in terms of your interests,aptitudes and personality, which will help you make a wiser decision.
You can do this by giving a career test on http://www.youngbuzz.com/career-assessment/role-assessment-career-counselling
You will also be able to see a sample report of how your report will look like here. This will surely help you with an unbiased view about yourself and then deciding a career which suits your profile the best.