单选题 .  When choosing a job, you should consider what you would like to be doing 15 to 20 years from now. The job you choose will affect the future course of your life. You should know clearly your abilities, skills as well as your interests and aims. Be honest about your weak points as well as your strong ones. Take a good look at yourself, what you are good at, and what kind of person you want to be.
    The most important thing for you to consider is the immediate advantages against the long-term prospects offered by the jobs you are considering. Will the occupation you select give you satisfaction, not just when you start, but in the years to come? Realize now the importance of education in all fields, technical and professional. Remember that when promotion occurs, preference is usually given to educated persons—other things being equal.
    Talk about your job preferences with your parents, teachers and your headmaster. They can help you think about the jobs in which you will find satisfaction and challenge. It takes a very long time to find the work that suits you the best. Have a correct regard of your job. Is it just a means of getting money to do the things that you want to do? Is the work important to you and your future happiness and contentment?
    Your life-long job cannot be approached in an unplanned way. It must be considered carefully. Once you find your life-long job, you should do it with patience and wisdom.1.  In choosing a job, you should have a clear knowledge of ______.